SLx MD-21 ACSS CQB 5.56/.308

The SLx MD-21 is a next-generation micro red dot sight built for close range precision and durability. Weighing just 142 grams, it features a rugged housing and upgraded mounting hardware for rock-solid performance under pressure. For taller setups, it pairs seamlessly with the SLx 2.26” mount, ideal for night vision or heads-up shooting preferences.

The advanced LED emitter delivers a true Red Dot Bright™ reticle with complete night vision compatibility and ultra-long runtime. AutoLive® motion-sensing technology conserves battery life by powering down after two minutes of inactivity, then reactivates instantly on movement.

The ACSS CQB reticle combines a precise chevron with BDC dots, wind holds, auto-ranging marks, and a bold CQB ring, all in a compact red dot footprint. The reticle supports holdovers out to 600 yards for 5.56 or 7.62 NATO, while the horseshoe approximates the spread of 00 buckshot at 25 yards. Users can cycle between multiple reticle configurations, including chevron-only, chevron with BDC, or chevron with CQB ring.

Features:

• Autolive technology extends battery life
• Fully multicoated lens
• Top mounted push button controls
• Ultra bright ACSS-CQB reticle with 4 selectable modes
• Night vision compatibility
• Shockproof and waterproof aluminium construction
• Black anodized finish
• Includes Low mount and Absolute Cowitness mount with spacer (1.41" or 1.535" Height)
• Standard microdot footprint

This Primary Arms red dot sight is part of the SLx optics line. SLx optics have built a reputation for innovation, reliability, and value. All SLx optics undergo rigorous field-testing during development to best serve you in any environment.