ActiVHeat 12V Far-Infrared Heated Glove Liners and Tensioning Lanyard (LRG/X-LRG, 5-Level Heat Controller) You must use a compatible heat level controller and fused vehicle battery cable with this item as it gets too hot without a controller. These are the warmest gloves on the market today - capable of putting out 14 watts of infrared deep penetrating heat per glove or 28 watts per pair Touchscreen Feature Available for All Sizes (except X-Small) thin spandex based construction that conforms to your hand shape and allows the glove liners to be worn beneath most outer gloves Glove liners are energized by ActiVHeat carbon fibers bundles that emit far-infrared light waves to generate deep radiant heat that works on radiated heat than mere conduction as with metal-based heated garments.