Keep your toes nice and toasty while facing the cold weather with the Gerbing Heated Clothing 12v Heated Insoles. These insoles heat the entire surface area of your foot and reach up to 135°F with their Microwire technology. When you pair these with Gerbing Heated Clothing's Heated Jacket Liner (540-1029) and Pant Liner (540-1037) you'll be ready for any temperature mother nature brings your way.; Max temperature of 135°F Heats entire surface area of your foot 12v DC 0.8 amp Powered by Gerbing Heated Clothing battery harness 540-1075 & Y-Harness 540-1082 Works best with the Gerbing Heated Clothing On/Off switch 540-1087 Men's fitment: SM 5-1/2-8, MD 8-1/2-10, LG 10-1/2-12, XL 12-1/2-14, 2X 15-15-1/2 Women's fitment: XS 4-5-1/2, SM 6-7-1/2, MD 8-9-1/2, LG 10-11