The Aimpoint PRO (Patrol Rifle Optic) was designed with the input of current and former professionals to create the most dynamic Red Dot sight available. Featuring band-pass lens coating, the PRO is compatible with every generation of night vision devices and provides a crystal clear 1x image for quick target acquisition in close quarter situations. The modular QRP2 mount securely attaches to standard picatinny rails and includes a removable spacer that provides optimal height for co-witness with iron sights on carbine style firearms. Additionally, the QRP2 incorporates a torque limiting knob to completely eliminate over tightening. You won't need to worry about turning the battery on and off with the PRO. The 3-year battery life allows you to turn the unit on out of the box and leave it on for an always ready sight. Other features include a see through ocular lens cap and standard objective flip-up lens cap that are both recessed to prevent impact damage, a rugged 30mm tube, threaded objective bell for use of ARD (Anti-Reflective Device), 4 Night vision settings and 6 daylight settings, djustment cap retainers to prevent them from being lost in the field, and a ten year personal use warranty. Note: These no longer have the battery cap retainer strap.