Gen X-4 Heated Glove Liners - XL/2XL Elements heat entire length of each finger and thumb, Comfortable 85/15% Polyester/Lycra? liners fit snugly under existing windproof and waterproof gloves or mitts, Connect to 12V power source; provides 25W of heat and draws 1.8A, For use with GEN X-4 Warm Tek heated jacket liner: no additional hook-ups are required; simply plug directly into the plugs hidden in sleeve ends, Leverages ZEPTO? fibre technology, these heating fibres are so thin, wouldn't be able to notice if not for tremendous heat output, GEN X-3 and GEN X-4 are fully compatible., Use of a temperature controller is ., to use these liners under a waterproof glove.