Bivouac sack

A bivouac sack is like a sleeping bag that is like a very big blanket that you can crawl inside of. It is made of special materials that keep you dry and warm even if it's raining or super windy outside. When you go camping and sleep in a tent, you can use a bivouac sack to put over your sleeping bag to keep wetness and cold from getting in. It’s like a cocoon for you to snuggle up in and keep warm and dry when you're camping outside. It keeps you safe and warm even in the wild woods.