You don't have to know how a microwave works to enjoy a piping hot bean burrito and you don't have to understand the complex processes behind nuclear fission to understand why the Arc'teryx Fission Gore Tex Gloves will keep your hands warm. Ok, so there is no nuclear reaction going on inside these gloves, which is probably for the best, but they do deliver huge warmth, so your hands will feel more like that piping hot burrito, rather than the frozen variety.The Fissions are backed by a Gore Tex XCR membrane, which walls out heat robbing moisture and maintains a breathable feel, so your hands won't end up getting wet with sweat from the inside. A stretch softshell material helps the gloves maintain a breathable feel and keeps them comfortable and dexterous when you're fiddling with gear. The palm is reinforced with leather to keep them in one piece when dealing with abrasive pieces of equipment in demanding mountain environments. Three different types of PrimaLoft insulation along the back and palm of the hand help keep the gloves super warm while offering a dexterous feel in the palm that will retain insulating properties even if it has been packed out. Cinch the large gauntlet down to trap heat and keep snow out and lock down the removable wrist leashes when you want to keep the gloves close, but not on.