Does he mean bivy bag. Because that's usually where the word bivy comes in. A bivy (or bivouac) bag is simply a water-resistant (often made from Gore-Tex) tub that you slide into-dressed, or in a ...

Serious campers, hikers and long-distance athletes know that one of the best ways to stay fit and healthy as you move through the wilderness is by getting a good night’s sleep. A bivy sack (“bivy” is ...