Remote Control 3.7v Heating Insoles, Sock Pad. Feature: Keep Warm in Winter: Keep Warm in Winter, Preventing Coldness and Frostbite Can Be Cut: There Are Yardage Cutting Lines on Surface, Can Be Cut to the Desired Size According to Your Needs, the Arch is More Fit and Comfortable. Temperature Remote Control: Designed with Temperature Remote Control Device, Different Buttons on the Remote Control Are Used to Control Different Operation Modes, and the Temperature Can Be Controlled According to Your Own Needs. Battery Powered: Built-in Lithium Battery, Ready to Use when Fully Charged, No Need to Tie the Battery, No Need to Connect to Power Supply. Good for Heath: Release Far-infrared Rays when Heated, Promote Blood Circulation, Prevent Frostbite, Relieve Menstruation and Invigorate Blood, Relieve Fatigue, Etc. Specification: Name: Electric Heating Insole Material: EVA Voltage: 3.7V Battery Capacity: 2100 MA Charging Voltage: 3V-5V Power Output Efficiency: 98% Overcharge Protection Voltage: 5V Overload Protection Voltage: 2.85V Charging Method: USB Charging Size: 35-40, 41-46 (can Be Cut) Temperature: High Temperature Level 60-65, Use Time About 3-4 Hours, Medium Level 50-55, Use Time About 4-5 Hours, Low Level 40-45, Use Time About 6-7 Hours. Packing List: 1 Pair of Heating Insoles Remote Control*1 USB Charging Cable*1 . We are an international seller, your order will be shipped from abroad so please allow the necessary time of minimum 14 working days for delivery right now depending on where you ship to, due to ongoing delays in postal deliveries globally.