This is my jerven bag. It's survival bag, wind sack, tarp, bivvi bag, sleeping bag, camo cover for hunting all in one.
This particular model is the Jerven Thermo hunter. It comes with a built in Polyamid liner, which helps against condensation as the outer fabric is aluminum covered polyester.
It comes in 5 differnt colors. Signal orange, mountain camo, woodland camo, desert camo and white/snow camo. Mine is the mountain camo.
Rescue helicopters, the Civil defence, the Red Cross, the Military, domestic
and abroad, foreign rescue departments, etc. have taken the Jerven bag in
use as rescue equipment. The reason is simple enough. The Jerven bag
retains the body heat better than the traditional woollen blankets, etc.
Also it is very popular with hunters.
I use mine mainly as a bivvi/sleeping bag. The measurements as a sack is 220x100 cm. As a tarp 220 x 200 cm an weghs 1500 gram. But lighter models exist.
It has separable heavy duty zippers on 3 sides, and zippered openings for the arms, when using it as a poncho, or for hunters on "ambush" posts
which is the prefared method for most moose and reindeer hunters in Norway. As they can sit with their arms out, free to use their rifle. It comes with a pair of loose armlets as well,
so you don't have to have wet armes if raining. They are also good for protection against blood when butchering. I.ve used them when cleaning fish.
I think it should be suitable for a hammock as well, and I plan to test that this summer. Probably just make myself a hammock frpom some cheap tarp, and hang it inside the bag.
Anyway here are some pictures....