Meprolight M21 Reflex Sight Review


The Meprolight M21 Self-Powered Reflex Sight is capable of light-powered aiming, all without the need for a battery. During the day, the red dot sight uses a collector system made of fiber optics that focuses the light and tritium radioluminescence at night. Though the Mepro M21 is not capable of quality night vision, it can be augmented with a night vision lens to give it that capability.

It is also capable of quick targeting with both eyes thanks to its large 30mm diameter lens. The sight was developed in collaboration with the Israeli special forces. The military technology implemented in the sight makes it the first close-combat lens in the world. It also has a Picatinny steel mount that maintains a perfect zero on quick release, enhancing its accuracy.

Product Highlights

  • Features light aiming without the use of batteries
  • Designed in coordination with the Israeli Special Forces
  • The sight has been proven in combat
  • The sight includes a quick-release mount
  • Features crystal clear glass for quick target identification

What We like

The Meprolight M21 self-powered reflex sight allows for greater accuracy thanks to the high-quality lens. This makes it great for teams as well as individuals looking to make the best out of their guns. The speed, precision, and accuracy guaranteed by your gun make a world of difference in how you use it.

The Mepro M21 reflex (red-dot) sight is combat-proven, having been used by various military and law enforcement agencies across the world. This has been primarily driven by the company's commitment to integrating the latest state-of-the-art technology in their sights to make them more effective. For this reason, Meprolight has become the favorite dot sight supplier to defense and security bodies across the world.

Advanced technology has enhanced the M21 reflex optical sight effectiveness. The state-of-the-art technology gives the sight a rugged, multi-use dimension as it incorporates a red dot sight and lasers powered from a variety of sources. Thanks to technology, the sight allows the red dot to exceed expectations, hosting a red dot sight, infrared, and a visible laser in a single unit.

On aiming, the manufacturer has invested in energy-efficient technology to ensure the reflex sight is reliable for days at a time. The sight is capable of continuous operation on the battlefield for hours on a single battery. Even after the battery has been depleted, the sight can still be used without light.

What We Don't Like

The red dot sight often is not clear, sometimes looking splashy. Its red dot looks like a small bit of paint on a screen with residue smeared all over the rest of it. The bullseye reticle is large, taking up a lot of space. This makes the sight great for close-range shots though not very useful for long-range use.

Its performance in darker environments could also use some improvement. It does not use batteries or have a night vision feature, it relies on tritium for nighttime illumination. Once the tritium is used up, you will need to upgrade and add night vision, otherwise the sight become unusable.


  • Its light weight allows targeting to happen in nanoseconds
  • Features a large field of view for quick target acquisition and assessment
  • The sight is very energy efficient, working continuously for hours in battlefield conditions
  • High-quality glass that can be used in any weather
  • Features the latest advanced sight technology


  • Not very good for long-range targets
  • Does not work as well in darker environments
  • The reticle could be clearer in some instances

Frequently Asked Questions

Q: Should you be seeing double triangles on the sight?

If you are seeing multiple triangles, you may not be using the sight as intended. Ensure you have the settings on the sight well-calibrated. However, some people who have had eye surgery or are using corrective lenses do see double triangles. The key is to focus on the target as opposed to the triangles.

Q: Are there ARDs (anti-radiation devices like a kill flash) available for this?

Kill flashes do not come in the box with the sight unless the box specifically mentions that it does. Otherwise, no ARDs will be included in the box.

Q: What is the lifespan of the tritium?

Meprolight modern sights will function for about 12 years though you can expect service of about 9 to 10 years from the tritium vial. However, you do have the option of sending the sight to Meprolight for a replacement.

Q: What is the dot size in Minute of Angle (MOA)?

The inner dot is about 4.5 moa, with the outer ring of the bullseye circle being 15 moa. However, they can differ depending on the model of Meprolight M21 reflex sight you may have. Some models have an MOA of about 5.5 or 4.3. This makes it a lot more useful when used in close-quarter defense.

Q: Can I see in the dark with this Meprolight?

Since it's not a night vision scope, you cannot see in complete darkness. When using your sight, ensure you keep both eyes open. However, the sight uses tritium illumination technology and is night vision compatible which means you can add an attachment to augment it so you can see in complete darkness.

Final verdict

Having been developed with input from the world-renowned Israeli defense force, the Meprolight M21 features state-of-the-art technology. This has made them quite popular among military and enforcement agencies across the world. This sight is quite reliable in most cases, being capable of operating for hours in battlefield conditions before going out. However, it can still function without a battery.

As reliable as the Meprolight is, it still falls short in some ways. Despite being powered by tritium for use in the dark, its night vision capabilities are poor. The sight was developed to be the first close-range sight. Though it excels at close-range action, it is not the best choice for long-range use.

M21MeproMeprolightRed dotReflex opticTactical