Heated Gloveliners go inside your normal gloves and are heated using a rechargeable battery that fits into a stitched pocket on top of the Gloveliner. There are 2 different types of Warmthru Gloveliner: WT, the one featured on this page and G2. The main difference is that WT uses a heat element that is removable and replaceable whereas G2's element is sewn in.