Fit & Design: Knee-high heated socks with remote control and battery with charger Heating pad strategically placed on top of toes for superior warmth 3.7 volt battery that can be recharged Ultra-fine, soft fibers Curved, slim battery fits into a pocket for a low-profile fit Technology: Built-in heating panels and are made with ActionFlex material that provides lightweight warmth, comfort, and versatility How to Use: 1. Power Up - Charge the provided ActionHeat 3.7V batteries. 2. Plug-In - Connect the batteries to the cords located in the pocket on the top of the sock. 3. Turn On - Press and hold the power button on the battery for 3 seconds. Additional Details Includes - 2 socks, 3.7 Volt 2.2 AH Lithium-polymer rechargeable batteries, 1 remote control, 1 dual battery charger kit