A hard-anodized 30mm tube was utilized, enclosing a high efficiency circuit that allows the sight to be turned on and left on for up to three years using a single battery. The Aimpoint PRO Patrol Rifle Optic’s front lens utilizes a unique band-pass coating, which allows the sight to be used with all generations of night vision devices. The modular QRP2 mount includes a removable spacer that indexes the sight at the optimal height for co-witness with the standard iron sights on AR15/M16/M4 Carbine style weapons. This spacer can be removed to enable the use of the sight on police shotguns or sub-machine guns. The QRP2 mount for the PRO Optic also incorporates a torque-limiting twist knob that provides the optimal level of pressure on the rail while completely eliminating the possibility of over-tightening. Both the PRO Optic’s front and rear lenses are recessed within the sight body to provide protection against impact damage, scratches and fingerprints.