The Primary Arms SLx MD-21 (model 810027) is an advanced micro dot sight built to deliver exceptional CQB performance. Weighing only 5 ounces, it is both lightweight and rugged, with upgraded mounting hardware for guaranteed rigidity and precision.

Key Specifications

• Manufacturer: Primary Arms
• Model: Microdot (MD-21)
• Product Type: Red dot sight
• Magnification: 1x
• Reticle: 2 MOA red dot
• Lens Size: 21mm
• Illumination Control: AutoLive motion-sensing
• Weight: 5 oz.
• Emitter Type: Upgraded LED, night vision compatible

Frequently Asked Questions

What illumination technology does the MD-21 use? It uses an upgraded LED emitter with full night vision compatibility and a true Red Dot Bright reticle, plus AutoLive to shut the dot off after about two minutes of inactivity and turn it back on instantly when picked up.

Is a taller mount available for the MD-21? Primary Arms offers a 2.26 in. mount option for the MD-21 for use with night vision or a more heads-up shooting position.

Buy the Primary Arms SLx MD-21 2 MOA Micro Dot Sight

Shop the Primary Arms lineup or browse more of our Red Dot Sights selection at Schaefer Defense.