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Product Info for Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive & ACSS-CQB Red Dot Reticle, Black, 810028

The Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive & ACSS-CQB Red Dot Reticle, Black, 810028 Color: Black, Magnification: 1 x, Objective Lens Diameter: 21 mm, Reticle: ACSS-CQB, Illumination Type: LED, Illumination Color: Red, Adjustment Click Value: 1/2 MOA, Red Dot Emitter Type: Enclosed, Battery Type: CR2032, Lithium Metal, Weight: 5 oz, Red Dot Sights-Footprint: Not Applicable. is here at OpticsPlanet with unbelievable prices Up to 20% Off! Please also check out more options for Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive.

Purchase your new Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive & ACSS-CQB Red Dot Reticle, Black, 810028 from OpticsPlanet today and you will appreciate the easy checkout process, fantastic customer service, Free Shipping policy and information on easily tracking your order.

The SLx MD-21 is an advanced micro dot sight that incorporates the latest technologies and materials to deliver exceptional CQB performance. Weighing only 5 ounces, the SLx MD-21 is both lightweight and rugged, featuring upgraded mounting hardware for guaranteed rigidity and precision when you need it most. If you are looking for a taller mount, check out the SLx 2.26in Mount for use with night vision or if you prefer a more headsup shooting position. The upgraded LED emitter offers complete night vision compatibility as well as a true Red Dot Bright reticle with an ultra-long runtime for full operability in any environment. Additionally, the Autolive technology shuts off the reticle when no motion is detected for two minutes and immediately turns on as soon as you pick it up.

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.

Features:

Autolive technology extends battery life

Fully multicoated lens

Top mounted push button controls

Night vision compatibility

Shockproof and waterproof aluminum construction

Standard microdot footprint

Included Accessories:

Low mount and Absolute Cowitness mount with spacer (1.41in or 1.535in Height)

Features of Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive

  • Autolive technology extends battery life
  • Fully multicoated lens
  • Top mounted push button controls
  • Night vision compatibility
  • Shockproof and waterproof aluminum construction
  • Standard microdot footprint

Package Contents:

  • Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive
  • Low mount and Absolute Cowitness mount with spacer (1.41in or 1.535in Height)

Specifications for Primary Arms SLx MD-21 Push Button 1x21mm Micro Reflex Red Dot Sight w/AutoLive & ACSS-CQB Red Dot Reticle, Black, 810028

Color Black
Magnification 1 x
Objective Lens Diameter 21 mm
Reticle ACSS-CQB
Illumination Type LED
Illumination Color Red
Adjustment Click Value 1/2 MOA
Emitter Type Enclosed
Battery Type CR2032, Lithium Metal
Weight 5 oz
Red Dot Sights-Footprint Not Applicable
List: $249.99 (Save 20%)
$199.99
Order Now & Earn $20.00 OP Bucks
Code: 29R-RD-CSP6-810028
MPN: 810028
UPC: 818500018261
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Last updated 2026-07-28 UTC.