Durable, doesnt' cook when you're next to a fire, quiet in the bush, breathes well in subzero to let the sweat out, yet when relatively thick acts as a pretty good windblock, deflects snow off the lower layers and you can just beat it out in camp and it sublimates dry quite nice in dry subzero cold.

Not so hot once it's above zero (C).

Mines made of a red heavy denim-like cotton, more like canvas than denim. A bedsheet would probably suck, I want mine to deflect bush and the like - not shred.

My personal preference is more towards cotton duck/denim/canvas for such a thing. However unlike the traditionalists I think you can do fine with a more modern *breathable* nylon (not goretex) for a similar application if you aren't worried about burning it near a fire, or the noise it makes on brush. All this really is
is a light breathable (in subzero temps) garmet to deflect wind, snow, brush, and spindrift from fuzzy warm breathable as heck base layers (with me, multiple layers of merino, cashmere, and fleece but anything appropriate like that can do). the key thing is to cut the wind and deflect snow but stay very breathable and easy on easy off so you can exert yourself and adjust so you're not getting wet.

Note this is for, well, running around in the bush, in very cold weather, where the snow doesn't stick to everything because it's wet. it isn't for digging snow caves. it isn't for wet deep snow. it's for weather like you get in alberta in the deep winter, (or sweden or finland) - then
this works well.