The Hotronic Heat Elements with Cambrelle Covers are the perfect way to customize your footwarmers. Simply install the Hotronic Heat Elements on your favorite custom insoles or orthotics, apply the soft self-adhesive Cambrelle Insole Cover for extra comfort, plug-in to your Hotronic Battery Pack, and experience the joy of Hotronic! Plus, if your insoles need a little resurfacing, the Cambrelle Covers will bring back the feel of a smooth new surface. We also carry the entire line of Hotronic Products!