This adjustable arm band with reflective panel is small and lightweight. It offers convenient protection to its wearer. Panel lights up with the touch of a button and emits a bright glow for added visibility. Full light and pulse settings. Battery life of 80 hours.CR2032 battery 3V. Adjustable straps. CE certified. Panel lights up with touch of a button. CR2032 battery 3V. Battery life of 80 hours. Retail bag. Bright compact and lightweight.