UTG® ACCU-SYNC® 2521R Dot Sight, Red 3 MOA Single Dot, for Mini ACOG®


UTG® ACCU-SYNC® 2521R Dot Sight, Red 3 MOA Single Dot, for Mini ACOG®

ACCU-SYNC dot sights

UTG® ACCU-SYNC® dot sights come in a compact and subcompact size and feature a red illuminated 3 MOA dot with 8 manually adjusted brightness intensity settings to choose from. Illumination memory conveniently gets users right back to the last brightness setting used upon activation. Fully sealed, ACCU-SYNC® dot sights are IPX7 waterproof rated and constructed from matte black anodized 6061-T6 aluminum. Optimized for low power consumption and powered by a single CR2032 battery, a 30,000+ hour battery life (at middle brightness) comes standard.
The mounting base uses the common mini ACOG® footprint and is configured for a lower 1/3 co-witness out of the box. Removing the included riser drops the height down to that of a low mount providing users two commonly used height profiles for different firearm applications. In addition, the base features squared recoil stops and our QR (quick release) mount, making for a quick installation and removal, reliable return to zero, and is compatible with Picatinny rails with widths that may even be out of spec. Tool-free tension adjustment is locked in place via a gear and spring-loaded locking lever interface, allowing users to set it once and forget it.

in stock
  • Precision Machined from 6061-T6 Aluminum and Finished in a Matte Black Anodization
  • Wide Field of View 20mm Lens Diameter
  • Impact Resistant Tempered Glass Lens
  • 3 MOA Red Dot with 8 Brightness Settings
  • 30,000+ Hours Battery Life at Middle Brightness Setting
  • Snag-free Flush Turrets with Crisp 1 MOA Per Click Adjustment at 100 Yards
  • IPX7 Waterproof Rated
  • Low Profile Quick Release (QR) Mini ACOG® Mount with Lower 1/3 Co-witness Riser Included
  • NOTE: We recommend to tighten the M5 screw with torque value of about 25 inch-lb.
  • Low Profile Quick Release (QR) Mount with Tool-free Tension Adjustment
  • Configured for a Lower 1/3 Co-witness and Mini ACOG® Footprint Compatible
  • Snag-free Flush Turrets with Crisp 1 MOA per Click Adjustment at 100 Yards
  • Multi-coated Lens with Wide 20 mm Field of View
  • IPX7 Waterproof Rated
    Operation Range from -40°F to 158°F
  • Recoil Rated Up to .450 Bushmaster
    Squared Recoil Stops for A Secure and Repeatable Zero
  • Locking Quick Release Lever Prevents Inadvertent Release
  • Precision Machined Matte Black Anodized 6061-T6 Aluminum Construction
  • Reinforced Main Body and Recessed Windage and Elevation Turrets
  • Impact Resistant Tempered Glass Lens


Target Dot reticle consists of a single floating dot in the center as the aiming point with the least visual distraction. It is commonly used for quick aiming applications with lower demand for pin-point accuracy. The shooter aims by pointing the dot at the target. For a reflex dot sight based on light reflection, the sight usually does not have magnification and there is an unlimited eye relief. The dot is a reflected image of the light source with common characteristics from any light reflection, including possibly slight flare and fuzziness of the dot.


DISTANCE (YARDS) 25 50 75 100 200 300
DOT SIZE BY LINEAR DISTANCE (INCH) 0.79 1.57 2.36 3.14 6.28 9.42


  • Neoprene Dot Sight Cover
  • M5x0.8-5mm Length Button Head Screw, X2
  • Allen Wrench 3mm
  • T25 Torx Wrench
  • W/E Adjusting Wrench
  • CR2032 3V High Energy Lithium Battery
  • Cleaning Cloth
  • User Manual


More Information
Materials6061-T6 Aluminum
Surface FinishAnodized
Parts IncludedCleaning Cloth, CR2032 3V High Energy Lithium Battery, Hex Wrench 3 mm, M5x0.8-5mm Length Button Head Screw, Neoprene Dot Sight Cover, T25 Torx Wrench, W/E Adjusting Wrench
Waterproof RatingIPX7
ReticleSingle Dot
Reticle Color(s)Red
Illumination Toggle Type+/- Digital
Brightness Settings8
Brightness Mode(s)Manual
Battery TypeCR2032 3V
Battery Life (hrs)30,000
Battery LoadingRight Side Turret
Click Value1 MOA
Linear FOV @ 100 yds3.77'
Eye ReliefInfinity
Lens MaterialGlass
Optic Footprint For Mini ACOG®
Mount to Rail Torque Value25 in-lbs
Weight (oz)189 g / 6.7 oz
Center Height (mm/in)1/3 Co-witness: 39 mm (1.54 in) | Low Mount: 25.4 mm (1.00 in)
Height (in)68 mm / 2.69 in
Length (mm/in)68 mm / 2.66 in
Total Mounting Space45 mm / 1.78 in
Width (in)42 mm / 1.67 in
Window Size (in)20 mm / 0.79 in
1Neoprene Dot Sight Cover1
2M5x0.8-5mm Length Button Head Screw,x2
3Allen Wrench 3mm1
4T25 Torx Wrench1
5W/E Adjusting Wrench1
6CR2032 3V High Energy Lithium Battery1
7Cleaning Cloth1
8Optics User Manual1


Leapers, Inc. warrants that all products conform to published specifications and are free from defects in material and workmanship. Leapers, Inc. will repair or replace, at our discretion, a defective product for the duration of the product’s lifespan. In the event of a product being discontinued, credit for the product’s MSRP may be offered.

⚠️WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm.
For more information go to www.P65Warnings.ca.gov.