5.56" overall. Water resistant. Impact resistant. LED with TIR lens. 18650 battery (1500 lumens, 1.5h runtime),123A battery (1200 lumens, 1.25h runtime). 250m beam distance. Thumbscrew mount attaches quickly and securely to MILSTD-1913 rails. Charging cord included. Requires (1) 18650 battery (included) , or (2) CR123A batteries (not included). Aluminum construction. Color: Black. Boxed with hanging tab.