4" overall. Weapon mountable. Two white LEDs plus one 5mR laser. Visible up to 22 yards. Integrated rail key. Detachable keyring. Push button on/off switches on back of housing. Can be mounted on pistol, rifle or shotgun. Fits MIL-STD 1913 (Picatinny) rail. Uses two 2016 batteries. NOTE: Batteries that are included may be expired. An extra set of batteries have been included. Synthetic construction. Color: Black. Hang packaged.