Primary Arms Lower 1/3 Cowitness Micro Dot Riser Mount

Manufactured by Primary Arms
MPN: 910054
Manufactured by Primary Arms
18 Reviews

In Stock

Standard orders will ship out in 1 business days or less if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination. NFA items will take longer to ship and are dependent upon ATF processing times.

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The Primary Arms Lower 1/3 Cowitness Micro Dot Riser allows for a lower 1/3rd cowitness on AR15 and similar platforms when combined with any Primary Arms Micro Dot, as well as many other standard Micro dot designs. When looking down the iron sights, the red dot will be placed in the bottom part of the Micro dot’s scope tube. The lower 1/3rd cowitness setup allows a less obstructed view of the entire scope tube when using the red dot instead of the iron sights. The light weight design, constructed of anodized aluminum, is easy to install. The riser features a lifetime warranty.
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BrandPrimary Arms
Mount HeightLower 1/3 - 1.65 in
Optic SeriesClassic
Optic TypeAimpoint T2
PlatformM1913 Picatinny
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to

Ratings & Reviews

18 reviews


A Terrific Product from a Great Company!


I recently purchased an MD-ADS red dot sight from this company.This is really an exceptional product for what it costs.The company always ships promptly and delivers what it advertises.Thanks Primary Arms.

Excellent Product


Just a perfect riser. Easy to install and works as designed. Really can't ask for anything more.

Micro dot riser


Just installed, looks great. Solid quality and fast shipping.

Good bang for the buck


Simple and nicely built with a very good price point. Wish they would do a QD version of this.

Great service as always


This mount isn't the best out there and is made in China but it gets the job done. Would no hesitatate to buy again if I need a non quick detach mount.

Primary Arms Lower 1/3 Cowitness Micro Dot Riser


Worked excellent! Great customer service!

It works but....


I would avoid this and go with the Primary Arms 3 post riser...this one ended up flying off my pistol AR after a few rounds and sent my red dot flying...luckily the red dot was okay but the screw that holds the riser mount I guess its a decent mount except for the hardware included....

Micro Dot Riser


I had purchased this riser LMH-2L13 for the PA Micro Dot MD-RBGII. I removed the four screws on the removable base and removed it. I installed the new riser mount and had applied blue Loctite and tightened down the screws but noticed that they were too long for the base by about 1/16" allowing the red dot to move side to side. I called customer service at PA and spoke to one of their technicians and he suggested that I try filing down the screws or finding some small washers to try and make it fit. He said if I couldn't remedy the problem contact PA and he would send shorter ones to me. I ended up fitting tiny washers onto the screws and got the two to mate up correctly. A little extra leg work for this setup because the PA removable base and the riser base are not the same thickness. I have it installed on my rifle and it looks does look good and customer services was excellent in trying to solve the fitment issues.

Very happy


I was afraid it was flimsy or wouldn't stay on but it rocks. Great value and happy I bought it.

Red Dot mount works great.


Bought this mount for my PA Red Dot. Matches up perfectly with my PA magnifier. The 1/3 co witness looks great using my iron sights with magnifier flipped to the side. Primary Arms sells great products.