Size: L Easy to use: simply press the button for 3 seconds and the vest heats up accordingly. The front and back can be controlled separately by adjusting the BELLY- and BACK buttons. | 3 temperature settings. This electric vest has 3 temperature settings to choose from: Blue light 30-35 C (energy-saving mode), white light 40-45 C (comfort mode), and red light 50-55 C (warm mode). | 4 heating zones. With integrated carbon fiber wire and 4 therapy pads, the heated vest generates heat over the neck, center of the back, and under two pockets that keep the body warm, promote blood circulation, relieve pain, and relax muscles. It's perfect for use in the cold winter! | 5 V/2 A USB charging. This electric thermal vest is powered by a 5 V/2 A external battery, and its USB connector is compatible with most power banks on the market (power bank must be purchased separately). A fully charged 10000 mAh power bank can heat up to 8 hours. Additionally, the external battery can be with a universal mobile battery of 5.0 V/2.0 A. | Premium and safe. The heating vest is made of polyester fiber and hollow cotton, and the heating elements are made of carbon fiber, they are soft and radiation-free. Hand washing is recommended. Machine washable in cold water, air dry (do not spin or wring). Warm and sweet gift. The heated vest is lightweight, warm, and health care, ideal for different outdoor activities like snow hiking, skiing, camping, fishing.