The Mepro M22 PRO features a factory-installed light module that eliminates reticle washout and enhances low-light performance. With cutting-edge fiber-optic illumination for daylight visibility and premium Swiss-manufactured tritium vials for nighttime clarity, this sight operates seamlessly in any lighting conditionno batteries required (unless you want it).Tritium glows at a certain brightness level 24/7/365. Meprolight engineers designed a battery powered mechanism to enhance the reticle in extremely lowlight. The single CR2032 battery provides over 50,000 hours of use. The auto-adjuster reacts to ambient light to maintain a crisp reticle in the worst conditions. Do you need it for the M22 to work? No. It is there to mitigate the effects of adverse conditions. The transition between fiber-optic and tritium systems is instantaneous and automatic, ensuring youre always ready. Built with rugged, battle-proven construction, the Mepro M22 PRO meets or exceeds rigorous standards to perform flawlessly in the harshest environments. Its reliable in all weather conditions and compatible with night vision devices (NVDs) and magnifiers for added versatility. With a ten-year warranty on tritium luminance, the Mepro M22 PRO delivers unmatched performance. Prepare for any challenge and ensure your survival with the unwavering reliability of the Mepro M22. Elevate your shooting experience and trust in a sight designed to perform when it matters most! Tritium luminance is warrantied for ten (10) years. Specifications for Meprolight M22 PRO 1x28mm Reflex Red Dot Sight: Manufacturer: Meprolight Magnification: 1 x Objective Lens Diameter: 28 mm Eye Relief: 10 - 600 mm Adjustment Click Value: 1 MOA Emitter Type: Open Weight: 0.58 lb Condition: New Lens Type: Glass Dimensions: 3.8x3.2x2.7 in Adapter: w/o QD Mount Features of Meprolight M22 PRO 1x28mm Reflex Red Dot Sight Factory installed light module eliminates reticle washout and improves lowlight performance 100% self-illuminated aiming solution; No batteries required Reticle illumination is auto-adjusted based on ambient light levels Compatible with NVDs and Magnifiers Compact, lightweight ergonomic design 10 Year warranty on tritium illuminance Package Contents: Meprolight M22 PRO 1x28mm Reflex Red Dot Sight