SureFire Titan Ultra-Compact LED Keychain Light Series Virtually indestructible, high-performance LED is regulated to maximize output and runtime at two useful levels: 125, and 15 lumens Proprietary faceted reflector creates broad, smooth MaxVision Beam that matches your field of view--and allows for better situational awareness Head switch - simply twist counterclockwise repeatedly to activate and set output level or turn off Powered by an included rechargeable AAA NiMH battery (charger sold separately); can also be powered by a readily available AAA alkaline battery and a AAA lithium battery Included stainless steel split ring on tailcap easily and securely attaches to keys