Stone Glacier is expanding their sleeping bag line with a quilt which features an open bottom. This saves weight as you sleep atop your pad and aren’t carrying the portion of the bag that compresses under your body. It can be pulled closed via the bungees at the rear.
The shell is 15 Denier Pertex Quantum Shell with DWR. The insulation is 850+ Fill Power HyperDRY™ 90/10 Grey Goose Down.
False economy. These designs save a tiny amount of weight but give up so much adaptability and function it just doesn’t stand up. Can’t sit up, cant roll around, restricted to certain mat sizes and shapes, no contingency if your mat fails. There’s a reason the idea has never taken off with hard climbers where 100g might make a difference.
Nice looking bags though I’d stick with the normal design.
I gonna call BS on this comment. Pads are the only insulation from the ground and mountaineers and climbers have been using designs like this for years.
Iggy,
You and Bob are debating the technical merits of this system at higher altitudes and for specialized users. I’m not going to get in the middle of that. I can tell you both that in the early 80s, the US Military replaced the Vietnam era “air mattresses” – that never held air for long – with closed cell foam roll up sleeping mats.
At least in infantry units at the time it was common to lay on the mat and pull a fully unzipped sleeping bag over you similar to how this design works. This was done with boots and clothing and sometimes even LCE on so that the soldier could be reasonably insulated from the ground, get some sleep, and throw off the bag expeditiously if necessary.
I can confirm that it worked pretty well in various temperate zone winters including 3 Team Spirit exercises (Jan-Feb) on Korea’s frigid ridges. Of course, doing it the way I described does not require anything other than a standard style sleeping bag. It also is not a technique I would recommend unless someone is facing an imminent tactical threat that requires them to be ready to spring into action at a moment’s notice.
TLB
Boom! Terry’s always dropping crucial knowledge bombs, and I’m here for it.