Keep this Emergency Bivvy to hand on your adventures on the outside chance that you are forced to spend a night outdoors, or even at home, without heat. It reflects 90% of your body heat to keep you warm, seals out rain, wind and snow and packs down small. Turned inside out it doubles as an emergency blanket and comes with an attached whistle for signalling and a tinder cord on the included stuff sack to start a fire. At 100g it is not going to weigh you down and may just save your life. Be prepared.