Product Description The Primary Arms Optics Classic Series 21mm Micro Reflex Sight delivers a daylight-bright 3 MOA green dot in a compact, low-profile housing purpose-built for micro-compact pistols. The 21mm objective lens and square profile minimize slide overhang while preserving a clear, unobstructed sight picture at 1X power. Built on an RMSc footprint, this sight offers broad compatibility with milled slides and popular adapter plates, making it an easy drop-in upgrade for everyday carry setups. The housing is machined from 6061 aluminum with a durable anodized black finish. AutoLive technology intelligently powers the dot off when the optic is stationary and activates it instantly upon motion, dramatically extending battery life without sacrificing readiness. A conveniently bottom-mounted CR2032 battery ensures easy replacement without removing the optic from the slide. Product Highlights 3 MOA Daylight-Bright Green Dot: Crisp, fast-acquiring green reticle visible in a wide range of lighting conditions for confident target acquisition. AutoLive Power Management: Automatically deactivates the dot when still and reactivates with motion, providing up to 40,000 hours of battery life on the medium illumination setting. 10 Illumination Settings: A full range of brightness levels allows the shooter to dial in the perfect dot intensity for any environment. RMSc Footprint Compatibility: Fits a wide array of micro-compact pistol slides and adapter plates for hassle-free mounting and everyday carry integration. Rugged 6061 Aluminum Construction: Anodized black housing offers lightweight durability suited for hard-use carry applications. Specs Brand: Primary Arms Optics Model: Classic Series 21mm Micro Reflex Sight MPN: 810049 UPC: 818500019947 Objective Lens: 21mm Magnification: 1X Reticle: 3 MOA Green Dot Illumination Settings: 10 Battery Life (Medium Setting): Up to 40,000 hours Battery Type: CR2032 (bottom-mounted) Technology: AutoLive Motion-Activated Power Management Footprint: RMSc Housing Material: 6061 Aluminum Finish: Anodized Black Type: Micro Reflex Sight Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer. ]]>