In “Sack” part one, we reviewed the truly nice and tiny but somewhat fragile emergency bivvys made by Adventure Medical. Well here is that guy’s older brother, and Junior is awed.
At only 13.6 oz (384 gr), Guides SilSack is still truly portable, yet it’s made from silnylon that’s durable enough to use every so often for a lunchtime storm umbrella or emergency shelter. The footprint is about 5’x7’x2′ — big enough to easily fit two humans, and three in a pinch. Plentiful nylon lash tabs make creative setup a cinch. For example, it’ll set up using skis stuck in the snow, or as a tarp in the trees. A couple of end vents prevent suffocation when in sack mode (though care with air supply would still be important if you really sealed this thing around yourself in a storm).
Downside with all silnyl bivvy sacks is they’re incredibly slippery. Thus, wrapping up in one while sitting or reposing on awkward terrain can be a challenge. While sculpting a snow pit or shelter, engineer accordingly.
I’m realizing that having a quiver of bivy sacks is a good idea for an active ski mountaineer. For tough trips with smaller groups I’ll probably grab the smaller Adventure Medical version, but once the crowd grows or becomes a guided mission I’ll be packing the SilSack. Thumbs up to Integral Designs for their minimalist practicality!