Features Comfortable and wear‑resistant, not easy to pilling, delicate and soft, warm and durable. Equipped with two 4000mAh large capacity batteries, you can keep warm up to 11. 5 hours ( low temperature range ). Three gear heating settings, including low gear ( 45 ℃, 11. 5h ), medium gear ( 55 ℃, 9h ) and high gear ( 65 ℃, 6. 5h ). One minute rapid heating, can withstand- 40 ℃ cold. Machine washable and hand washable. Remove the battery before washing, but do not wring it out by hand. Specification- Color: Black/ Grey ( Optional )- Material: Cashmere- Size: One fits all size- Battery capacity: 4000mAh- Battery type: lithium battery- Output voltage and current: 3. 7V, 2A- Input voltage and current: 5V, 1. 5A- Charging time: 5H Note: Please allow 1- 3cm ( 0. 4- 1. 18" ) difference due to manual measurement and slight color variation for different display setting. Package Including Package list: 1 pair heated socks 2 pcs batteries