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Primary Arms  |  SKU: PA-SLX-MD-21-ACSS

Primary Arms SLx MD-21 Push Button 21mm Microdot w/ AutoLive, ACSS-CQB Red Reticle - PA-SLX-MD-21-ACSS

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$199.99

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Description

Primary Arms SLx MD-21 Red Dot Sight – ACSS-CQB Reticle

The SLx MD-21 takes micro red dot performance to a whole new level with the proven ACSS-CQB reticle—a smart, compact solution designed for everything from point-blank defense to long-range precision. Weighing just 5 oz., this rugged red dot is built for serious shooters who demand speed, accuracy, and durability in a lightweight footprint.

The new ACSS-CQB reticle is a game-changer in the micro dot world. Featuring a precise chevron aiming point, three BDC holds calibrated for 5.56 NATO or 7.62 NATO out to 600 yards, wind holds, and a CQB horseshoe, this optic delivers unmatched versatility. Whether you're clearing rooms or ringing steel at distance, this reticle has you covered. Best of all—you can choose between four reticle modes to match your mission:

  • Chevron only

  • Chevron + BDC

  • Chevron + Horseshoe

  • Full ACSS-CQB reticle

The upgraded LED emitter ensures night vision compatibility and daylight visibility with 12 brightness settings, and Autolive™ motion-sensing tech automatically powers down the optic after 2 minutes of inactivity—then powers it back on the moment you move it. Built with fully multicoated glass and a hardcoat anodized aluminum housing, the MD-21 is both waterproof and shockproof to handle harsh environments with ease.

Need a taller mount? Check out the SLx 2.26" Mount (sold separately) for heads-up shooting or night vision use.

Key Features:

  • ACSS-CQB reticle with BDC out to 600 yards, wind holds, ranging, and CQB horseshoe

  • 4 reticle modes: Chevron only, Chevron + BDC, Chevron + Horseshoe, Full Reticle

  • Autolive™ tech for extended battery life

  • Night vision compatible with 12 brightness settings

  • Fully multicoated lens for enhanced clarity and light transmission

  • Top-mounted push-button brightness controls

  • Waterproof and shockproof aluminum construction

  • Standard Microdot footprint (Aimpoint Micro compatible)

  • Includes Lower 1/3rd and Absolute Co-Witness mounts

  • Backed by the Primary Arms Lifetime Warranty

Specifications:

  • Weight: 5 oz

  • Battery: CR2032 (3V Lithium Coin)

  • Brightness Settings: 12

  • Click Adjustment: 1/2 MOA

  • Finish: Hardcoat Anodized

  • Material: Aluminum

  • Mount Compatibility: Aimpoint Micro, M1913 Picatinny

  • Reticle: Red ACSS-CQB

  • Night Vision Compatible: Yes

  • Warranty: Lifetime

Part of the proven SLx series, known for innovation, reliability, and real-world performance. Every SLx optic is field-tested and duty-ready—no guesswork, just results.

There is no sales tax, unless you live in GA/IL/IN/MI/NJ/NC/OH/PA/VA/MD/NV/AZ/KY/UT/FL/MN/TN/WA/AR/CO/CA/PR/WV/MO

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