Heats up to 140°F and lasts up to 8 hours. Easy to use the wireless remote control with 3 heat settings. Integrated heating system with built-in 3V rechargeable batteries. Ultra-thin and lightweight design for maximum comfort. Fits in all types of footwear, shoes, and boots. Heating System: 3V. Deodorized breathable fleece lined softshell fabric. Estimated Heating Time:. High: 140°F - 3 Hours. Medium: 120°F - 5 Hours. Low: 100°F - 8 Hours. Includes:. Two Rechargeable 3V Insoles. Dual micro-USB charging cord. Wireless remote control. Accessory storage bag. Instruction Manual. How to Use:. Charge Up - Fully charge insoles with provided charger kit (the battery is built into the insole). Pair Up - Pair the remote to the insoles. Turn On - Press and hold power button on remote of back of insoles to turn on power. Select Heat - Choose (H)igh, (M)edium, or (L)ow heat level on the remote. Insert - Place insoles in shoes or boots.