"The Holosun ARO-RD2 Reflex Sight with HM3X Magnifier is the complete package for short- and mid-range targeting. The ARO (Advanced Rifle Optic) is the next evolution of Holosun's popular 20mm 403 and 503 Series optics, featuring the all-new 22mm housing that pairs perfectly with the HM3X Magnifier. The ARO features Holosun's premium anti-reflective glass along with Shake Awake technology that brings the unit to life with motion and preserves battery life by shutting down when it senses inactivity. The HM3X Magnifier enhances the utility of the ARO-RD2 by providing 3x magnification for longer shots. The HM3X has a generous 2.75"" of eye relief and features a quick-release, ambidextrous, flip-to-side mount that keeps the unit out of the way when you don't need it. HM3X Magnifier includes spacer. ARO-RD2 Reflex Sight includes 1.05"" mount, 1.63"" mount, multi-tool, wrench, and cleaning cloth.ARO-RD2 Reflex Sight: 22mm housing Premium anti-reflective glass 10 daylight and 2 night vision brightness settings Shake Awake technology Up to 50,000 hours battery life Rugged aluminum housing ½ MOA adjustments for windage and elevationHM3X Magnifier: Provides 3x magnification Quick-release, ambidextrous, flip-to-side mount Rugged aluminum housing IP67 waterproof rated"