These LED flashing reflective light-up armbands come with a closure and two CR2032 batteries pre-installed. You can activate the LED Lights with three flashing modes: fast blinking, slow blinking or steady onoff at night or in misty weather. The closure makes it easy to fasten this type of armband onto your arm or leg. The closure also makes this band nearly a one-size-fits-all. This reflective armband is very useful as a safety band for cycling, marathons, jogging, walking, camping, travel, sporting events, and any other outdoor events. Imprint your logo on the armbands to promote a safety me