US "Woobie" Poncho Liner, Woodland, Unissued

Converts into a sleeping bag

After being introduced, the rain poncho & liner combination soon became the standard-issue sleeping gear for hot climates or general summer use. It's very simple to make a summer sleeping bag of the two:

• Tie the liner to the grommets of the poncho
• Snap the poncho sides together to make a tube
• Get in and sleep

The US Army states that the lowest manageable temperature is about +10°C / 50°F, i.e. a proper Indian summer rating.

Note: This woobie is also compatible with the British jungle sleeping bag!

The Varusteleka Rain Poncho with a pocket and Särmä TST L6 Rain Poncho are a bit more narrow than the woobie, but they have grommets in the right places if you're fine with a somewhat sloppier coupling.

Works as a thermal cape and underblanket

The Woobie is essentially a light on-the-go thermal & camouflage cape or an ad-hoc blanket to make the best of situations where you can stop to take a nap. The fact that it's easy to quickly throw off in a hairy situation fits well into military purposes but the ease of use definitely helps hiking and outdoor life in general. The Woobie is also usable as an extra insulation with "proper" sleeping bags.

If you're into hammocking, this thing can work as an underblanket. If the tie strings aren't enough, it's easy to modify them. You could get two and tie them together for extra warmth.

The only thing the Woobie lacks, funnily enough, is a hole in the center for your head, so it can't actually be worn as a poncho with a rain cape. Some adventurous users have made a slit in the center to rectify this. However remember to reinforce the cut seams and do make a little insulation flap on it. This can also be as simple as two hook-n-loop strips.