... technology from Cree USA, 80lm/watt· Focusable Lens: Narrow and Wide Beam,1cm adjust lens range· Adjustable Duo-Mode Brightness ... Visibility: Approx. 2 miles, depending on atmospheric conditions and line of sight· Power Source: Uses 3 standard ... workers· Home / Auto / Airplane / Boat emergency light· Instrument and watch illumination· Military, Police, Emergency Tactical Operations· Hunters, Hikers, ...