Turn up the heat whenever you want with the Chi Vest Adjustable Heat Wearable. Intelligently designed, this vest has smart functionality to keep you cozy in any weather. The Chi Vest has five heating pads with two in the front and three on the back. Using the built-in controls, you can select one of three temperature settings ranging from 104F to 167F. In addition, you can also control these zones separately for the ideal heating every time. The Chi Vest is available standalone and works with any standard 5V power bank. Or, you can opt for the set with an 8-hour rechargeable power pack. which also charges your phone. The Chi Vest is perfect for everyone. The vest is also beneficial for relieving pain in your back and body. The Chi Vest has a thin material design. This way, you can wear it under other clothing if you wish. Finally, the vest comes in two sizes and has 3D adjustable sizing with optimally placed zippers and buttons.