Features: 1. 3 Speed Temperature Control: Low temperature 35-45C, medium temperature 45-55C, high temperature 55-65C. 2. 11 Heating Zones: Electric heating vest covers 11 heating zones, built-in with quality carbon fiber heat elements, rapid heating in three seconds, with strong insulation. Generate consistent heat for your neck, back, abdomen, and waist, etc. helping to maintain body warmth, promote blood circulation, and relieve pain as well as tension in muscles. 3. USB-Powered: With a USB interface, if powered by a 10000mAh power bank (not included), this heated vest is capable of retaining warmth for up to 6-8 hours. 4. Machine Washable: Because the heating wire inside is made of carbon fiber wire, it can be easily cleaned in the washing machine, also hand washable, please note that do not wring out by hands. 5. Multiple Size Optional: M, L, XL, 2XL, 3XL, 4XL, 5XL optional, please check if the size fits you before purchasing. Specification: Material: Polyester Product Color: Black Product Size: M, L, XL, 2XL, 3XL, 4XL, 5XL Product Weight: 650g Package Included: 1 x USB Heated Vest