Primary Arms Classic Series 21mm Micro Reflex Sight - 3 MOA Dot

Mounted on a 10mm G40. Nice low profile and holds zero well. 10mm is a punishing round. So far, so good.

I settled on the 21mm micro mounted on an EGW mount for a S&W M&P 22 Compact because of the gun's narrow slide width and the Micro's very light weight, so as to not interfere with slide recoil causing FTEs. It matches-up perfectly (NO slide overhang), not too tall, and zero function problems with CCI Blazer ammo. I really enjoy the wide range of dot brightness selections. It's a small screen, but that works for me on this gun for my purposes.
VERY reasonably priced especially considering the lifetime warranty.

You can't go wrong with the price. Not to mention the lifetime warranty. Glass is very clear. red dot is very accurate. It's perfect on Canik MC9. Highly recommend this product for your micro carry!

I mounted this optic to my Sig Sauer P365XL and have nothing but great things to say about it! This red dot is spot on, has great adjustable brightness levels, and has held zero after hundreds of rounds and consistent concealed carry use. On that note, the optic is a great size and is very comfortable for a daily concealed carry. The construction is also a nice durable metal instead of polymer like comparable red dot sights.

The only improvements that I could recommend to PA is possibly adding shake awake functionality and/or solar cells to the top.

If the features you only use 2 times a year really matter to you i guess this isn’t for you. But for the people that live in the real world and conceal carry, this is for you!
The window size is awesome for a rmsc. I have a 407k and the window size is better than the 407k. Reviews say its not bright enough but thats nonsense. Plenty bright and with a (not as strong) aluminum, this allows for a bigger window!
I could buy 2 for the price of a holosun. Recommended 4 star only because it is not enclosed.

It does fit the hellcat rdp without a plate. It has the same RMSC footprint as other red dots. Mounts directly to the gun. Make sure to buy the additional screws they sell for it which only costs $8.

I just leave mine on. Didnt take much to get it set at full co-witness. dropped right in just fine. comes with different mounting screws. thank god, because i needed two different lengths due to a pin on the r7 mako. but it works and works great. love me some primary arms!

Nice optic mounts up great on a hellcat. M4s for the hellcat not included though so either gotta buy or make your own. Not too sure on how well it holds zero though as my hellcat is extremely tough to keep zeroed (me or the firearm not sure). My slide lock also was not locking open all the time either, not sure if it is my mags or the weight of the optic will have to remove and try again. I recommend this product if you have a reliable firearm to install it on

The optic fit right into my hellcat pro. Like other reviews, the screws were about 0.1mm too long. While I could have added a base plate, I added small washers between the head of the screw and the optic. I now have a tight, snug fit with a clear picture.

This is a $150 optic, so it is not expected to have the additional features of a Trijicon or Holosun. You get a SOLID optic (aluminum housing) that you can rack, check, and anything else you would typically do with a RDO and be confident in it's ability to perform (don't cry about the bottom mount battery, 40k hour battery life).

I can confirm the supplied m4 optic screws fit the optic perfectly for the dagger micro slide. Actually, a better fit than the PSA supplied long screws. Also holds zero quite well and keeps the pistol well concealed and carries well.