The Meprolight MPO-DF Reflex Sight is an open reflex red dot sight specially designed for full-sized pistols.This cost-effective optic punches far above its cost. It features a 3.5 MOA ret dot reticle, RMR footprint, automatic and manual brightness controls, CR1632 battery lasting 2 years plus while being water, shock, and fog proof makes this optic stand out from the crowd.The Mepro MPO-DF allows you to upgrade your current sighting system with money left over for more ammo. FeaturesRMR FootprintAutomatic and Manual Brightness AdjustmentsShake Awake Power Saving ModeIPX7 Waterproof RatingRMR Footprint5 MOA Red Dot ReticleCR1632 - 15,000+ hours battery lifeMIL-1913 Picatinny adapter included Includes:1x Low profile Picatinny mount1x CR1632 battery1x T10 Allen wrench & 1x3mm Hex wrench2x #6-32x92x 4-40x7.21x Rubber dust cover1x Cleaning Cloth1x User Manual