Description The A-Spec M3 is manufactured to be compatible for uses with a Shield RMS-C® footprint, and it boasts a red auto-brightness control reticle to accommodate shooting at any time, day or night. This optic is perfect for subcompact guns, and is notoriously durable – aluminum alloy housing, IP55 water-resistant, shockproof, able to withstand up to .375 H&H caliber and operate in temperatures from -22F to 122F. With a battery life up to 100,000 hours and an included rubber cover, low-profile fixed mount and manual, the A-Spec M3 is guaranteed to help you Make Your Mark. Features - Fits pistols with Shield RMS-C® footprint - Auto-brightness control reticle - Cowitness with standard pistol sights - Red reticle illumination - Lightweight compact aluminum alloy housing - Rugged aluminum alloy housing - IP55 water-resistant - Shockproof - Battery life up to 100,000 hours Included in Package - Rubber Cover - Low Profile Fixed Mount - (1) CR2032 Battery Batteries Used - Type: CR2032 - Quantity: (1)