Features:Three heating modes: USB interface, power adapter, and power bank. Easy to use, just put in the shoes and connect the power to enjoy the warmth. Soft and comfortable, with exquisite workmanship. Heating is stable, and safety is guaranteed. Heating pad can be cleaned, be sure dried before use. Specification:Condition: Brand NewMaterial: Soft LintColor: BrownHeating Time: 10 MinsOptional Size: 35-36 (23x8x1cm/9.1x3.1x0.4in)37-38 (24x8x1cm/9.4x3.1x0.4in) 39-40 (25x8x1cm/9.8x3.1x0.4in) 41-42 (26x8x1cm/10.2x3.1x0.4in) 43-44 (27x8x1cm/10.6x3.1x0.4in)Three heating methods:1. The USB interface is heated, and one end of the USB power cord provided with the product is connected to the computer USB interface, and the other end is connected to the insole.2. The power adapter is heated, one end of the power supply is connected to the insole, and the other end is connected to the adapter.3. The mobile charging treasure is heated, one end of the power cord is connected to the insole, and the other end is connected to the charging treasure. You can enjoy the warmth anytime, anywhere.Package List:1 * Pair of Heating InsolesNote:The default power of the heating pad is 5V/2A. If your charger power is not 2A, it may result in non-heating.Powered by charger the heating power is 6-7W, if using the special adapter, the heating power will be 10-11W, 40% more heat than the charger does..