Warning: These socks get hot. Follow instructions and use them carefully.Experience the ultimate luxury and heated comfort with the ActionHeat Heated House Slipper Socks. With our unisex design, you don't need to suffer from frozen toes anymore! The ActionHeat 5V battery-heated house slipper socks are the perfect blend of quality and comfort. The Rechargeable ActionHeat socks reach a maximum temperature of 150F and can last up to 5 hours. ActionHeat battery-heated apparel utilizes innovative technology designed to warm the core body temperature. These revolutionary garments feature built-in heating panels and are made with ActionFlex material that provides lightweight warmth, comfort, and versatility.ActionHeat heated garments use FAR infrared heating and ActionWave heat reflective technology to deliver hours of heat and comfort. ActionHeat allows you to stay warmer and enjoy outdoor winter activities longer than ever before. HOW TO USE: Power Up – Charge the provided ActionHeat 5-Volt batteries. Plug-In – Connect the batteries to the USB cords located in the pocket on the top of the sock. Turn On – Press and hold the touch-button control on the sock for 3 seconds. Press the button to cycle through the heat settings. Features: Built-In heating panels strategically placed on the sole of the foot use advanced ultra-fine fibers to provide superior heating performance Heat-trapping fabric provides maximum warmth, comfort, and versatility.  Touch-Button Control Technology (3 settings) Power System: 1 amp Battery Voltage: 5 Volt Machine Washable using provided mesh wash bag only (gentle cycle)  Heats 5+ Hours Unisex Fit Sizes Available: S/M, L/XL, XXL Estimated Heating Times: HEAT BLAST (Red): 150F – 3+ Hours Medium (White): 130F - 4+ Hours Low (Blue): 100F – 5+ Hours NOTE: Recommended to use low or medium settings. Heat Blast should not be used for more than 5 minutes at a time.Material Contents: Material Content: 80% Acrylic, 10% Nylon, 7% Polyester & 3% Spandex Ultra-fine carbon fiber heating panels. Includes: (2) ActionHeat House Slipper Socks (2) 5V Volt Lithium-Polymer Rechargeable Batteries (1) 24" Dual Battery Charger Kit ActionHeat 5V Battery Heated Slipper Sock