ActionHeat AH-SK-3V-W-L-XL Wool 3.7V Rechargeable Heated Socks 2.0 with Remote, L/XL

50% wool/ 48.5% cotton/1.5% spandex construction Integrated heating system provides up to 7 hours of warmth 3 heat settings: 100F on low, 120F on medium, 140F on high Includes rechargeable 3.7V batteries with dedicated pockets Remote control for easy heat output management Machine washable without batteries