Three heat settings: red highest, white medium, and blue lowest Size: 59 * 21.8 cm Fast-heating Knee Pad: Heats in seconds, provides ultra comfy hot therapy for knee pain relief and injury recovery, keeps knee warm, can also be used on calfs, thighs, arms to relieve muscle soreness and cramps 3 Heat-settings: Easy to operate, you can control the heating temp and time totally by yourself. The power button with LED indicator, it can be operated to red-highest, white-medium, blue-lowest temp setting. Short press the button for once can change to another heat setting Adjustable and Stay in Place: With 2 bifurcate straps design, and hook and loop closure, the heating pad can wrap around and be locked at any leg or arm position where you need heat compress, you needn't hold it by hand anymore. With a built-in mash bag, put an ice bag in, you can use it for cold therapy if necessary USB Cord: Portable to use, it can be pluged in any power supplies with USB port, such as power bank, PC, laptop, desktop computer, car charger, and the heating temp can be various for these power sources with different output currents. The AC adapter with a fixed output 7.9V/1.1A is for quick heating and higher heating temp use Knee Heating Pad is portable, easy to put it in your suitcase or handbag. NOTE: Please don't use on bare skin in case of being burned. We will address any issues with product.Please feel free to let us know at the first time.