The ActionHeat 5V Battery-Heated Base Layer Shirt is revolutionizing the world of heated clothing. With its sleek, sophisticated look, which allows it to be worn as a base layer and as an outer layer underneath a heavy jacket or vest, it is both fashionable and functional. Piling on layers can be uncomfortable and unstylish. This shirt provides a lightweight, cozy solution to cold weather woes, so you remain warm and comfortable in all conditions - rain, shine or snow. Features: Safe heated technology Waterproof membrane Touch-button temperature control Machine washable - gentle cycle 4 LED power indicators Tri-zone heating system includes 3 built-in ultra-fine carbon heating panels strategically placed on the chest & upper back to warm core body temperature Good for heating fingers & thumbs Temperature Settings: High (Red): 130F - 2+ Hours, Medium (White): 110F - 3+ Hours, Low (Blue): 90F - 4.5+ Hours 2 amp power system 92% polyester; 8% Elastic Polyurathane Includes: ActionHeat Base Layer Shirt, 5V power bank 6000mAh & USB charging kit Instructions: Charge Up: Fully charge the power bank with the provided USB charger kit. Plug In: Connect the power bank to the USB plug located in the pocket. Turn On: Press and hold touch-button control, located on the chest, for 3 seconds. Press the button again to control temperature. This shirt is proof that you can have it all: warmth and style! Try ActionHeat technology today! *Please read all warranty information, warnings, and care, storage and usage instructions prior to wearing.