SURIVE EXTREME CONDITIONS: The Survival of the Fittest bivy sack is a reusable emergency sleeping bag that is designed to keep you warm alive in the most extreme circumstances. Engineered for survival and made for adventure these survival sleeping bags are an essential piece in any emergency kit. | PROTECTION THAT WORKS: Designed for survival our emergency sleeping bags are both water and windproof blocking out harsh rains, winds, and snow. Constructed from high quality mylar also known as biaxially-oriented polyethylene terephthalate (Bo-PE) these emergency sleeping bags also come ultra-durable prepared to perform in the most rugged environments. | ULTRA LIGHTWEIGHT: Made for adventurers by adventurers we understand the importance of size and weight. No one wants to lug around a large bug out bag, so don't! Our emergency bug out sleeping bag weighs only 0.3 lbs. and when rolled into our stuff sacks these sleeping bags will fit in the palm of your hand. Slide this emergency bivy bag into your glove compartment and make it a part of your car survival bag gear. | PARACORD DRAWSTRING and SURVIVAL WHISTLE: Our emergency waterproof sleeping bags also come with a high-decibel emergency survival whistle. When stranded deep in the woods relying on your voice alone to call for help just won’t do. The high frequency sound that is emitted from our whistle can pass through rain, wind, trees and snow ensuring that if someone is even remotely near, you will be heard and rescued. | MULTI-PURPOSE: Whether you're backpacking, hiking, bivoac, or out at a picnic our bivy bag serves many purposes. Not only is it a sleeping bag portable blanket, it can also be used as a poncho, tent, sleeping bag liner or a cover to keep your gear dry, a mountaineer's best friend. The possibilities are endless, get creative!