1ADJUSTABLE DESIGN: Running LED armbands are adjustable in size and stretchy for long hours of exercise without discomfort and can be worn on the wrist, ankle and arm. 25 COLOR LIGHT: LED light up band features a unique 5 color light design that reflects light, making it highly visible and safer for twilight and nighttime activities. 33 LIGHTING MODES: LED armband has three lighting modes, fast blinking, slow blinking and constant light mode, with one touch control to choose any preferred mode. 4WATERPROOF DESIGN: Rechargeable LED armband is designed to be waterproof and wrapped in PVC, so it won't get wet from rain or sweat after exercise. 5USB CHARGING: LED armband uses USB charging, which is relatively fast and powerful, and can last up to 10 hours of continuous use. 6APPLICABLE SCENES: Night safety light up band is the perfect accessory for outdoor night sports such as cycling, jogging, running gear, camping and hiking.