Every hunter has a go-to jacket. "Old dependable." The jacket you always take along because it’s the best you have for warmth. Meet your new Mr. Reliable - the Calor Jacket with Heatwave Technology. Using advanced scientific reactions, the Calor Jacket works with your own body heat, however little that may be, to warm you beyond anything you’ve experienced. We’d explain further but it’s probably best you just try it out for yourself.