"Welcome to the most powerful heated sock on the market! The ActionHeat 5V Battery-Heated Cotton Socks for Men have the highest tested performance of all ActionHeat items. Powered by FAR infrared heating and ActionWave heat reflective technology, these heated socks reach a maximum temperature of 150°F and can last up to 5 hours. Built-in heating panels, made with ActionFlex material, provide lightweight warmth, comfort, and versatility. Easy-to-use touch-button temperature control with 3 settings. Made of 70% cotton/30% spandex. Includes two 5V lithium-polymer rechargeable batteries and a 24"" dual battery charger kit. Machine wash. Imported.Manufacturer style #: AH-SK-5V. 70% cotton/30% spandex Powered by FAR infrared heating and ActionWave heat reflective technology Reach up to 150°F for up to 5 hours Touch-button temperature control with 3 settings Includes 2 rechargeable batteries and a 24"" dual battery charger kit"