Top 3 survival needs, Food, Water and Shelter. For comfort I would want a good knife and fire as well to help build and construct tools but to maintain your core temperature a Survival Blanket is something you can wrap yourself up in to prevent heat loss and stay dry. For building a shelter they are invaluable to reflect back the heat of a fire and keep the moisture off. SOL offers 2 blankets, the Survival blanket for 1-2 people and the Emergency blanket for one.
This SOL Survival Blanket is most advanced emergency blanket on the market - meticulously designed never to fail when you're counting on it with your life. It all starts with the material, vacuum-metalized polyethylene, that reflects 90% of your body heat while also offering a number of other important features that set it apart from traditional mylar blankets; it opens easily and will not shred if nicked or punctured, rips and tears can be repaired, it is quiet and won't crinkle in high winds, and its high-visibility orange exterior makes it easy for rescuers to find you. Plus, survival tips and techniques are printed directly on the blanket so you have them when you need them. Sized to fit two people.
Elmer Fitzwillie notes;" An emergency blanket is a life saver. Not only can you wrap up and stay out of the rain, conserve heat, and make you easy to spot if lost but it can be rigged in a shelter to reflect heat back on you or to make a Mors Kochanski Super Shelter.This blanket will work for 2 people and is tougher and more tear resistant than the $1 mylar blankets. This is a 4 oz item that is invaluable in a survival situation."