Smart heated cotton vest Selected high-quality cotton planting base; carefully selected materials; healthy and skin-friendly: soft; warm; not easy to deform. 1. Open the pocket and connect the USB with the portable battery. 3. Press lightly to shift gears and adjust the temperature in three levels. 2. Press and hold for 3 seconds to start heating. 4. Press and hold the switch or remove the portable battery to turn it off. 【New Smart Heated Vest】DOACE heated vest is one of the best home/outdoor care products that can be used as multiple thermal packs with unlimited energy to keep your body warm all the time. If you're going to be spending time outdoors this fall and winter, whether you're hiking, fishing, biking, camping, hunting, or attending sporting events, a heated vest is the best way to stay warm for longer periods of time outside. 【9 Heating Zones with Neck Warmer】Professional heating vest adds more heating zones, compared to other old heated clothes, they only have 3-5 heating zones, the new heating vest covers 9 larger heating zones, Built-in quality carbon nanofiber heating element due to its fast heating technology, lightweight, flexible and safe to use. Produces continuous heat for multiple parts of the body such as neck, back, abdomen, shoulders, waist, etc., wrapping your body in comprehensive warmth 【Safety Guaranteed and Requires Universal Battery Pack】Built-in thermal protection module. Once overheated, it will stop until the temperature returns to the standard level, ensuring 100% safety during use. It's compatible with common power banks with standard USB ports, allowing you to choose a high-storage power bank or prepare multiple batteries in advance.