The Tact Bivvy Compact Sleeping Bag is a warm survival tool to add to your survival kit or camping gear. This lightweight bivy sack can be used by itself, or act as a sleeping bag liner to keep you sound asleep. Features: Ultralight 4.7 oz HeatEcho™ technology reflects 90% of your body’s heat back to you 100% Waterproof, Tear-Resistant, and Windproof. Para-tinder paracord 120-decibel whistle. 3 Available. 1 for 15. All for 40