3.7V Heated Socks Foot Warmers for Men And Women， Electric Heating Socks， Washable Battery Heated Socks for Winter Skiing Hiking Fishing Riding， Keep Grey Features:Wide Applications: These heated socks provide powerful warmth and comfort while riding， skiing， hiking， fishing， etc. Great for arthritis foot and chronically cold feet， giving you a warm winter.Powered by a pair of 3.7V rechargeable Li-ion batteries (contain)， the heat energy of the product is 35-55 .3 Adjustable Heated Levels: 3 levels setting heat controller to adjust your favorite temperature according to different temperature demands.This battery heated socks use composite fiber heating material， and built-in heating elements covers whole forefoot， which can stimulate the blood circulation， and keep you warm all day.Heat quickly and you can feel temperature in 30 seconds. Keep your feet warm and healthy in winter.Made from 100% cotton material， these socks are absorbent， breathable， washable and quick-drying. Super comfortable， thick and durable.Specifications:Battery Voltage: 3.7 VoltCapacity:2200MahColors Available: Black， Gray(optional)Unisex FitDC interface: 3.5*1.35mmMaterial: 100% CottonSize: 28*23*9cmPackage size: 14*10*5cmPackage weight: 300gPackage Includes:1 Pair Heated Socks1 Pair battery1 USB