Measures 4" overall. 250 lumens with 2h 30m runtime. Silver finish commercial grade aluminum alloy body for improved durability. Customized optics design for impressive direct and peripheral vision. Neutral white LED produces light that is more comfortable to view than light from more common cool LEDs. Digitally regulated outputs include regular, power saver, and emergency strobe. Uses 3 AAA batteries (included). Impact resistant. Hang packaged.