The Meprolight M21 Day/Night Self-Illuminated Reflex Sight provides constant, all-light aiming capability, without the need for a battery supply. Reticle illumination on these Red Dot Sights is achieved by a protected fiber optic light during the day, and by a self-powered tritium light source at night. the Meprolight M21 Tactical Sight features a large 30mm diameter lens that provides rapid target acquisition and a quick-release Picatinny mount.

Meprolight M21 Reflex Sight Features 

• Designed for CQC
• FOV: Unlimited with both eyes open
• Rapid target acquisition
• Protected fiber optic light collection for daytime
• Self-powered tritium light source for night
• Reflexive, parallax-free aiming 
• Self-illumination adjusts to ambient light
• Reticle designed to be visible under all conditions
• Large 30mm diameter lens with state-of-the-art coatings assures large FOV
• Highly durable and rugged
• Sight is black and grey, 
• Increases accuracy and speed 
• Quick-release Picatinny mount 

Aiming Point Diameter

Meprolight M21 Specs 

• Magnification: 1 x, Fixed
• Objective Lens Diameter: 30 mm,
• Type: Fiber Optics/Tritium
• Illumination Color: Red,
• Eye Relief: 10 - 600 mm,
• Adjustment Click Value: 1 MOA,
  
• Parallax: 0.25,
• Lens Material: Optical Glass,
• Optical Coating: AR Coating,
• Light Transmission: 50 %,
• Attachment/Mount Type: Picatinny,
• Operating Temperature: -40 - 131 Fahrenheit,
• Water Resistant Mark: 1 m,
  
• 4.48 x 2.16 x 2.75 in, with Picatinny adaptor
• Weight: 13.12
• Aperture: 27 mm,
• W/E Travel at 100 Yds: +/- 35 MOA.