The Kemp USA Mylar Blanket is a lightweight multipurpose first aid blanket for body warmth maintenance, emergency shelter, protection from the weather, or reflective distress signal. The aluminized non-stretch polyester reflects body heat back to the user and stays flexible in freezing temperatures. Extremely lightweight and compact. Easily into first aid kits, hip packs, pockets, bags, and glove compartments. Windproof and waterproof. Mylar is a material developed by NASA for outer space exploration. It reflects back 90% of the body heat back to the user, works great as an emergency shelter, and also can be used as a reflective distress signal.