Losing body heat is a major cause of death in emergencies. The Emergency Survival Mylar Thermal Blanket can increase your chances of survival in all weather, all seasons and all circumstances. It is made of durable insulating Mylar material designed by NASA for space exploration. It retains / reflects back 90% of body heat. It is reusable, waterproof and windproof.The Leberna Emergency Survival Mylar Thermal Blanket is extra large in size, 130X210CM. Wrap around the body (leaving the face exposed). It is intended as an emergency shelter and can be used for camping, hiking, and surviving the cold outdoors.The Emergency Survival Mylar Thermal Blanket comes with 2 packs. Each pack is individually wrapped and weights only 2 oz. The dimension of each pack is 11*2*8cm. It is easy very light weight and easy to carry and store in your car, back pack or together with your emergency kit.That is how it is designed by NASA for space exploration. Even though the size of the sleeping bag or blanket is big, they can be folded into a very small size.