The PowerTac E4 is the ultimate everyday carrying key chain light. It combines a compact size and 30 lumen maximum light output with only one AAA battery. It's durability, shock resistance and rugged build quality make it the key chain light to go everywhere your adventures take you.
Tightening the head will turn the light on. Loosening it by 90 degrees will turn the light off.
DO NOT mix old and new batteries or different brands. This could result in explosion.