
Day Two of a traverse through the Gros Ventres outside of Jackson, WY. Sun softened mank with a heavy pack. We covered 60 plus miles over three days while exploring a new alpine arena. Photo: Clark Henarie
Examining the latest addition to the Scarpa Family
Written by Adam Fabrikant
This past February, I arrived home to a pair of boots sitting on the doorstep. I have yet to take them off. I was intrigued by this newer lighter boot, one that could offer a game changing ski touring experience built upon the well-received Scarpa Alien RS — the F1 LT.
This new boot had big shoes to fill as a replacement to a modified Dynafit Vulcan I’d used exclusively for seven years prior. A little about me, 5’ 8”, 135lbs. I work as a ski and mountain guide and ski full time. My ski season typically starts in the Chilean Andes in October, followed by winter in the Tetons and Greater Yellowstone, and then spring in Alaska. All of my skiing is human powered; I rode lifts two days this season while teaching an avalanche course. I enjoy long days, 10+ hours with lots of vertical and mileage. Living in Wyoming we joke that we get our miles as well as vert.
Since acquiring the F1 LT, I have skied them exclusively over some 50+ days. In terms of numbers for vertical/ mileage just assume I skied them more in the last few weeks than most will do in a season. These boots have skied the Grand Teton, Middle Teton, South Teton, Nez Perce, lines on Mt Owen, Teewinot and many other Teton High Peaks. I went on a hut trip in the Centennials out of West Yellowstone and recently did a three day traverse in the Gros Ventre Range in them. They’ve seen lots and lots of powder skiing and a good amount of technical rock and ice climbing. So, is the F1 LT my new do it all ski boot? Read on.
Alien, F1 or…Super Alien?
The design of this boot is simply a blend of two well-received Scarpa boots. WildSnow’s first impressions from the OR show revealed that this boot is a baby of the F1 and Alien, but which one is it really?
The upper cuff is closed by a velcro buckle similar to that on the F1, with numbers that make it easy to see how tight you prefer. Currently “13” works well for me, with the highest number being 14. I have found it easy to open and close the cuff and see no need to mod the cam. I can even close the upper cuff without moving my pant gaiter up for short descents where I don’t care to tighten the power strap and adjust the tongue into place.
Borrowing from the F1, there is also a thinner “power strap” above the thicker, numbered velcro buckle. Initially I thought I would remove this as I had removed the power strap from my Vulcans instantly. However, on the F1 LT the power strap has a clear purpose. It helps keep the cuff closer to my skinny calf and therefore the boot skis better. I have grown to like the power strap in a boot this light and I have no intention to remove it.
The ski/walk lever has been improved from the Alien RS. It now has a spring and clamps down well. The interface can get iced up, though I have not had any major issues with it yet. This is probably the largest change from the Alien RS.
The F1 LT comes in at an advertised weight of 990 grams in a 27.0 compared to the 920 grams for an Alien RS, which begs the question: what do you get from these additional 70 paperclips/ grams?

Simplicity. Roughly 100 grams more than stock with my custom footbeds and shim.
One, a slightly reinforced upper cuff. This, along with the improved cuff closure and power strap, make the F1 LT ski roughly 30% stiffer and more progressive than the race-inspired RS. They walk identical to the RS.
You also get a slightly more complicated transition. Instead of the RS’s one motion flick, the F1 LT is a 3 step process taken from the F1. Fine by me. I do not race and as the ski runs and climbs in the Tetons are long, I am typically not rushing my transitions. If you plan on yo-yoing short laps, the need to streamline transitions may be more important, an easy mod would be to remove the upper power strap.
The BOA closure for the lower part of the boot has not been changed from the Alien RS. This is my first ski boot with a BOA closure and it works fine. For me if the BOA failed it would not be a big deal; for short descents, or when my feet are tired I don’t even clamp it down. I understand the benefits of a BOA compared to traditional buckles, but it definitely does not lock my heel down as well as a good old buckle would.
Overall I would call this boot a super Alien rather than a FL LT… It walks like an Alien, does not look or feel like a traditional ski boot and still has the Alien marking on the rubber sole…Super Alien. I definitely have a future in marketing.

Committing turns on the Spooky Face, Nez Perce, Grand Teton National Park. Day two in the boots for me and they were working well.
The last few weeks have been transitional with the need for different skis. I have paired these boots with three different Black Crows ski setups including:
Navis Freebird, 102 underfoot, 169, Dynafit Expedition, Pomoca Race 2.0 (pink)
Anima Freebird, 115 underfoot, 176, Dynafit Speedturn, Pomoca Climb 2.0 (yellow)
Nocta, 122 underfoot, 177, Dynafit Superlite 2.0, Pomoca Climb 2.0 (yellow)
My first few days in the boots were with my old intuition pro tour liners, after about 5 days or so I was able to get the stock liners molded and have skied them since.
Liner
Scarpa uses Intuition Foam in their stock liners which is great. In my experience intuition liners are warmer and more comfortable than most others on the market. In the past, I have had to replace my stock Dynafit liners on day one, which is expensive. The F1 LT liner is more robust than the Alien RS Liner, but skimpier than the F1 liner. At 210 grams (sans footbed, but with stock spoiler) it is light, however the upper cuff and the tongue have a nice rigid feel. The cuff has velcro and it comes with a built in adjustable spoiler. The velcro allows you to either make the spoiler higher or lower depending on the height of your calf. I have been using the spoiler thus far and enjoy the forward lean for downhill skiing. After a month of hard use the liners are packed out and if ski shops were still open I would be trying to mold a fresh pair of Intuition pro tours; they’re significantly heavier but provide more support and would take up more volume.
Fit
I typically ski 25 boots, but after having tried on the Alien RS and finding them too tight to ski, I decided to upsize the F1 LT to 26. I have small, skinny feet with a few issues. I have had frostbite on my big toes twice in the last two years and I have neuromas, nerve pain in my feet from too much time in boots. The 26.0 fit me well out of the box. If anything they are probably a little too big and if I could I would try on a size smaller to see if the heel retention could be improved, but still long enough to keep my toes happy. I put a boot shim underneath my custom footbed to take up more volume which has helped. I have done no other modifications besides traditional liner molding. My toes can wiggle around freely, which as a ski tourer trying to log big days is a trade off I am ok with.
The F1 LT is a little wider in the lower shell than the Alien RS, roughly 99-100mm last. For some, myself included, the narrow last of the Alien RS was too small for long days. By making the last bigger, this boot will likely fit more people better.
Uphill performance
This is hands down the best walking boot I have ever put on, better than Dynafit PDGs and TLT 5s (possibly the best boot ever?). Last week when walking 22 miles on a ski traverse with lots of flat travel, I felt as if I had the right tool for the situation. At 72 degrees, the range of motion front and back is insane and the numbers don’t do it justice. With just fabric in the tongue and lower cuff section above the heel pocket, there really is very minimal resistance. I do not “bottom out” when leaning back on the flats and the gradual resistance when leaning forwards is perfect for steep skinning. The huge forward range of motion matches well with my expedition bindings that do not have heel risers.
I skin with the BOA and upper cuff fully open. For technical climbing I have fooled around with different options. When climbing Nez Perce, moderate fifth class rock with crampons, I decided to stay fully open which worked fine.

Proper rock climbing, Nez Perce, the F1 LT excels as an alpine climbing tool. Photo: Clark Henarie
A few weeks ago when climbing the Grand Teton via the winter normal route, Stettner-Chevy, I decided to close the upper cuff, tighten the BOA and keep the boot in walk mode. That worked well for moderate ice climbing.

Climbing the Grand Teton via Stettner-Chevy. The options for heel retention with different buckle configurations is great for ice climbing. Photo: Clark Henarie
Downhill performance
The F1 LT shines on the skin track, but what about the down? Although lightweight, the boot has some punch to it. The cuff wraps tightly around my calf, important for ski performance in minimalist boots. As a small man, these feel stiff enough for most conditions. The torsional rigidity is great, when edging on firm snow they feel solid. On firm snow with no surprises they ski great, 50° hop turns no problem.

Torsional rigidity that inspires confidence as I make my way down the classic Briggs/Stettner route on the Grand Teton. Photo: Clark Henarie
The boots hold up fine for fast skiing in good snow. They do not have a ton of progressive flex, but more than most boots within this weight class. However, when things got variable, I got tossed around a bit. This is partly due to the fit of the boot, but also because there is just not much material around my foot and ankle to absorb the bumps. While skiing the Apocalypse Couloir a few weeks ago I encountered firm and variable wind pressed snow, I was still able to ski aggressively and fast but it felt a little looser than I prefer.

The classic Apocalypse couloir, challenging conditions– the F1 LT was up to the task. Photo: Beau Fredlund
Durability
One issue with any ski boot in the 1 kilo category is durability and the Alien RS was known for its lack of it. Last spring on Denali and Foraker, one of my partners had the Alien RS, he broke the cuff closing mechanism, a piece of string, and he was scrambling to make his ski boots work well. My partner on the Grand Teton a few weeks ago had the Alien RS on and he was dealing with a similar problem, broken string… The interface between the gator and the lower boot has been known to be an issue in the RS, improved upon for the F1 LT, but still a potential issue.
By replacing the string with a more traditional cuff closure, Scarpa seems to have alleviated this particular issue, but I have found other weaknesses worth mentioning.
First: cracks have formed in upper cuffs of both boots. Both shells have these cracks in the same spot, I can hear the plastic clicking when I am skinning sometimes. One boot has cracks on both pieces of the orange overlap plastic. They do not seem to be growing in size.
Second: leak potential between the built in gator and the lower boot is something I’ve noticed (and friends that ski the Alien RS have brought to my attention). This area seems to be holding up well on my boots so far, but buddies have had to seam seal the interface over time.
I have been testing the F1 LT with really wide skis and therefore generating more force on the boot. Realistically they pair best with my 102 underfoot Navis. I pushed the boot far beyond what it was designed for by using wider skis in steep and deep terrain.
In a few weeks time when I get out my 91 and 76 underfoot skis, these boots are gonna feel beefy!
*Update from Scarpa: Adam had a pre production model. 20/21 Production models will attempt to address these two issues. We are optimistic that these mods, and keeping the skis under 110mm should help. In general the F1 LT appears to be a more durable upgrade to the Alien RS. See the photos and captions below*

The cuff wings will now taper down slowly to the same thickness, instead of the drop off where Adam’s cracked.

The pre and planned production gaiters. A rigid reinforcement piece will be glued to the edge of the shell for better adhesion. A lower height and higher ratio of flexible material will tug less on the glue. In our experience with the Alien RS, careful re-insertion of liners will help prevent glue failure
Bottom Line
So are they my ideal Vulcan replacement? Not totally. I’ve been on the one-boot quiver train for the last ten or so years, but I like the F1 LT enough to change my mentality. For me, this boot will eventually become the minimal half of a two-boot quiver. Once the world stops ending and December rolls around next season, I will want a beefier boot that can be my daily workhorse and lend more dependable durability to my larger powder skis.
At 1070 grams with liner, spoiler, footbed and shim, though, these things rip. If you want a free ride boot look elsewhere. If you want a boot that can ski the steeps, tour like a pair of running shoes and be enough boot for making GS turns, the F1 LT may be your ticket.
The F1 LT will be available to purchase Fall 2020. Shop for other Scarpa boots here.
Adam Fabrikant lives in Kelly, WY with his partner Erin and their dog Juniper. He works full time as a mountain and ski guide. He enjoys adventures to the far flung, making ski turns in absurd places, lapping powder like someone is going to take it away and endurance odysseys.
Beyond our regular guest bloggers who have their own profiles, some of our one-timers end up being categorized under this generic profile. Once they do a few posts, we build a category. In any case, we sure appreciate ALL the WildSnow guest bloggers!
38 comments
Some of us were concerned by a recent report that the shell was wider in the heel pocket area compared to the popular, benchmark F1. Can you comment?
Hey Nils,
I pulled out the caliper briefly on an Alien RS and F1LT, and could not find a difference in exterior shell width. Will hit the garage and confirm a few more measurements now. I find the Alien RS and F1 to be very similar in the heel, with the Alien much tighter in the midfoot.
since the alien RS is being discontinued, and the F1 LT is the replacement for the RS, it would have been nice to get a review from someone that had spent at least one day on the RS. Many folks considering the F1LT will be coming from the RS, with its tolerable but demonstrated shortcomings, and particularly interested in a real comparison.
I mean, on what basis does the author make this assertion :
“One, a slightly reinforced upper cuff. This, along with the improved cuff closure and power strap, make the F1 LT ski roughly 30% stiffer and more progressive than the race-inspired RS. ”
You’ve made it clear that you have no way of knowing this from personal experience. If you’re repeating 2nd hand info from someone else that’s skied both, then say so. If you’re simply regurgitating Scarpa PR, say so.
That crack on the orange cuff is a real concern. Happened to 2 pairs of the 3 RS I’ve used, and I was happy with the the Scarpa PR at boot release touting the reinforced upper cuff – assuming that they would address this obvious weakness. It’s ridiculous, and close to a deal breaker for me personally, that they didn’t.
Same with the gaiter interface. Sad that this hasn’t been improved. “a little seam seal” is overly dismissive of the nature of this issue and the difficulty of a lasting repair – if you’re going to put any real mileage on the boot.
Hey Buck,
Hope your doing well.
I have not skied the RS, as mentioned. I spent many days out on the F1 LT where my partners were on the Alien RS and we had many chats about the stiffness/ flex pattern. Just putting on the RS in a parking lot I was able to tell the change in progressive flex easily.
As for the gaiter interface, the issue is still present. Overall the fabric of the gaiter is not super waterproof, more water resistant. I do not see the interface as the main issue in my use so far. It seems the fabric would be the weakness if a true waterproof boot is desired.
As for the reinforcement in the upper cuff, this is in the rear section and not in the orange overlap area in the front of the shin. So unfortunately no improvement over the RS here in terms of cracking/ durability.
Thanks for the review, I am cautiously optimistic this may be the replacement for my faithful F1s. Is any info available about BSL? I have bindings mounted without adjustment plates and would prefer to keep it that way. But I am guessing this matches the Alien RS so I’d be out of luck on that front.
BSL will mirror the Alien RS exactly, same mold. Will try and dig that chart up for ya.
Hey Buck,
I am beyond excited to recruit Adam to review for WS, and also for this boot. As you can see he puts it to the test harder than most anyone would. I am one that has put a ton of miles on the RS and has broken pretty much everything on it. I also have a handful of days on the F1 LT. After editing Adam’s post, I felt like it was quite representative, and was good with publishing it as a valuable piece. The combo of thicker liner and more supportive cuff do yield some stiffness and progressive feel. 30% is higher than what I personally would feel-15ish, but the improvements may be more noticeable for Adam at 5’8″ 135lbs or being a different skier. Someone that spends as uch time trying on and modifying boots as Adam can get a good feel from the parking lot flex. Comparing an older, flexed out RS may factor as well. I notice that they soften substantially over a season, something the reinforced cuff should help with.
Can you fill us in on your RS usage? Skis, terrain, etc? Would be helpful to have that info as well here for others as a baseline. I never went as wide on the ski as Adam in my RS’, but pushing over 105mm and cranking GS turns or jumping off of stuff, I was understanding when I broke the BOA and cuff. My quick take on the F1 LT thus far is that it is a more durable RS that trades a slight impingement on walk and transition fiddling for a slight improvement in skiing. There are several more pairs floating around the WS team, and will have updates as we progress towards fall release.
For what its worth, Fabby has the acuity to know and “feel” how the RS skis without skiing it. I know this is difficult to explain and sounds incredulous though I prommise its true. He has a feel and understanding for skiing in the mountains that many of the most prolific regularly reach out to. Fabby spends a lot of time with many partners and has an lazer foccused and insatiably curious appetite for this thing we call ski mountaineering.
Well written article Fabby.
For all, see the updated photos above on the cuff wings and gaiter. The production model attempts to address both
I had to completely reglue one of the gaiter interfaces and partly glue the other in the pair. Not very many days, 30-50.
Scarpa was completely unhelpful on this and dismissive of the significance. It is a significant design/manufacturing defect in my opinion.
The other issues I have heard about: broken cords and boas I have not experienced. The boots were not skied too hard, always on skis 66-85 underfoot.
Just a note on regularly maintaining our high performance race cars and mountain bikes…
Ive never broken a cord on an RS in around 1,000,000 Feet over two winters. The 4 gram spare that I carried is still in my megar repair kit. I am convinced it is from taking care to help ‘set’ the cam pinch on the cord while closing the walk mode for the first time after adjustment of the cord. This prevents it from ever slipping or wearing much. It is physically impossible to break a 4 mil dynema cord by hand or foot unless it sees significant wear, which one should notice, during periodic gear inspection and then maintain before shredding the gnar or going on expedition. Just my two cents after a silly amount of miles and vert on every single alien model out there I believe! With all that being said It doesn’t matter much as the RS is gone! I stocked up! And I am mega stoked on the Scarpa F! Light!
one of the less desirable features of the F1 was that you had to undo the velcro everytime you go in and out….is that still the case? K2 has a good solution for this on their boots with a similar buckle…am hoping that Scarpa may have fixed this….since getting in an out of the RS is a breeze.
Please check the thread on TGR tech talk regarding a simple modification that allows the F1 main cuff buckle to be easily undone without touching the Velcro.
Hey Cam,
Unfortunately you still have to undo the velcro every time you get in and out of the boot…
Apologies for the TGR link, but as Nils said some folks on TGR came up with a pretty cool solution to avoid having to futz with the Velcro every time. Take a look at this, should be relatively easy for people to make their own.
https://www.tetongravity.com/forums/showthread.php/334615-Scarpa-F1-strap-buckle-mod-%E2%80%94-max-ROM
My F1 velcro wore out after less than one season and would no longer stick together when I put any tension on it with the buckle. I had to make some new straps out of Lange RX power straps. Working quite well, but I’m sure their lifespan is limited. Thanks for the link!
Cam, and all,
Sadly this is my only complaint of the F1 Light/F1 Its not that I don’t like the extra step (well maybee compared to the RS) but I find it difficult to make it accurate and repeatable. Im stoked t check that TGR trick thanks!
Teague
Thanks for the review Fabby!
Wondering if anyone knows how these boots are responding to bootfitting: is the bootboard removable, is the plastic workable?
Hey Max,
Hope you’re doing well. The bootboard is not removable. The plastic is workable, but on the Alien RS working the plastic voided the warranty. Overall not the easiest boot to work on. That being said, Gary went to town working on his Alien RS boots so it is doable.
I also have a low volume foot and the f1 neither holds my foot in the pocket nor does the liner tighten about my calf. Was hoping this new iteration would solve that, but your review seems to contradict that? Thanks for the review
I recommend drilling a 5mm ish hole at the end of the cracks to keep them from propagating.
Hey Ted D,
Have you drilled some holes to prevent the cracks from growing? Seems like a good idea.
It’s an old kayaker trick to keep cracks from growing … at least that’s where i learned it.
Hey Tim, The F1 LT is certainly more low volume than the F1. A very different boot, As Adam gets at here, it harkens much more to its Alien RS heritage. I have a ton of time in the F1 and Alien RS, stock this new boot will hold the heel and foot better in a direct comparison. Though I think it is smart in the long run to move this boot into the F1 category, which for branding purposes is the non-race light weight touring line. If you can find an Alien RS in your size, it will be pretty similar to how this will feel. The new liner is thicker and feels more supportive around the ankle.
Gary,
I would bet money that this boot will be widely reviewed to ski an par with the F1. I bet anyone tall, not heavy, and skiing on skis under 110 will suggest it skis markedly better than the F1. For me the RS skis better than the F1 on a 89×179 ski. I am certain theF1 Light will blow the F1 out of the snow in downhill performance. I have only been skiing easy during my ankle recovery. Cheers!
Hey Tim,
I find the heel fit to not be super tight. However, on the contrary the liner tightens well top my cuff with no gap what so ever.
Hope that helps.
Tim the F1 light fits more like the Alien RS. Narrow in the heal like the RS but a touch more room in the forefoot top of foot than the RS. You will like it better. Will still need a spoiler for skinny bird leg calves like mine but the cuff is significantly taller than the F1
It’s nice to see heavy duty testing which exposes the weak points in a product!
Regarding the heel fit issue, one trick I’ve used is to glue (Seam Grip) and gaff tape foam on the outside of the inner boot at the Achilles’ tendon wrapping to the sides slightly, sort of a bow tie shape. It’s best to test this before committing to glue.
Thanks for the great write up, excited about this boot. So I am one who the f1 fits perfectly but the RS is too narrow (in same size 26)which is a bummer because I would like a lighter everyday boot. I was hoping that the F1 Lt would be the answer. Anyone in this camp care to comment on people with wider feet fitting the F1 LT? Particularly if the normal F1 fits you good. Thanks!
Yes I’ve drilled lots of holes in various plastic and other materials to stop cracks from spreading, including ski boots. It works well, almost always stops the crack. I’ve even seen helicopter mechanics due it to doors successfully. Although they go one step further and drill holes along the crack and sew it together with stainless lock wire.
Looking forward to this boot! I have had mye eyes on the RS, but found it to be too flimsy. I still have my doubts about he boa closure, is seems very vulnerable and almost impossible to repair in the field. Was this the final retail version of the boot, or are there any chances Scarpa might still make modifications before general release?
ETTO
Ive broken one boa near the end of 1,000,000 feet in an RS. Zero while racing and adventuring on 4 pair of Alien 1.0, 3.0, new 1.0 as well. And I literally crank them down with nearly all my might (gloves on) and kick and climb in colorado/Teton etc. rock piles. I am a Boa believer. I can’t not be with that kind of reliability. For what it’s worth
Guessing will not come in 31.5? Increasingly difficult to find my size in this class boot.
Adam, Gary,
Thanks for the thorough review and continued discussion in the comments… I had a question about the liners…
You say, “The F1 LT liner is more robust than the Alien RS Liner, but skimpier than the F1 liner.” and then mentioned putting a pro tour into the F1 LT…
I tend to pack out my spring boot liners pretty hard, and have the desire to rejuvenate the fit and performance of these light boots with new liners. Personally I’ve found it impossible to get a Pro Tour (medium thickness version) into an F1… So I am curious as to your scheme to fit a pro tour into an F1 LT. Can you elaborate on your sizing and thickness scheme for this?
Thanks again!
Oh, I forgot to ask…
I’ve found the Pro Tour liner to be a great addition to certain boots, but I have also found that they do not walk as well as some stock liners, especially thinner or more flexible ones…
Can you speak to the impact that an Intuition Pro Tour Liner had on the walkability of the F1 LT?
Hey Kyle, We’ll see if Adam chimes in here. In my experience, the thicker replacement liners wont go in small boots until piping hot and soft during a heat mold. And an oven heat mold, not stacks. They’ll generally look a little wrinkled after on the outside, but should be smooth and fit well inside. Sizing wise, just apples to apples. I never down size simply to get a liner in there, because the stitched last in the boot will be too small, even after a good baking. Will certainly notice a slight restriction in walk range as compared to these, especially testing on the floor. While skinning, the leverage of skis overpowers liner materials provided the boot shell is as free as these babies. I am currently running a Maestrale liner in a Sportiva Skorpius- great match up. Skis softer at the beginning of the flex (more material between shin and rigid plastic tongue) yet is more progressive and holds my foot better. Slight impediment on walk is worth it. Just as you mentioned the stock liner couldn’t handle spring conditions.
No if only they would make a Meastrale LT, “spawn of Maestrale and F1” !
Ya Slim! I have some modding ideas for a hoped up F1, but something like the Maestrale Wave buckle on the foot of the F1 would do it wonders. Will certainly share any creation I come up with here on WS.
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