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Kit R - 4140/Check/SC

GMR

(11 reviews) Write a Review
$100.00
SKU:
Kit R - 4140/Check/SC
Adding to cart… The item has been added

Product Overview

This is our standard CHECKERED 4140 steel Super Safety with a machined detent that's been paired with a GMR Shallow-Curve™  trigger 

 

* Due to minor variations in manufacturers, some minor fitting may be required. 

Reviews

(11 reviews) Write a Review

11 Reviews Hide Reviews Show Reviews

  • 5
    Kit R - 4140/Check/SC

    Posted by CHRIS on Apr 21st 2026

    I ordered this for a 7 1/2" pistol build along with the H3 buffer offered here. So far it has been a great value for it's performance. Works fantastic. Customer service was excellent. Confirmation same day, tracking number the next day and package arrived a few days later.

  • 5
    Kit R

    Posted by Amish rake fight on Apr 19th 2026

    Excellent safety upgrade + great quality, slightly curved trigger profile is my new favorite

  • 5
    This thing is awesome.

    Posted by Jayson DeNoble on Mar 23rd 2026

    First off, I can’t believe how fast it arrived. Ordered on a Friday morning and arrived Tuesday afternoon. For context everything I’ve ordered from everywhere else, even local, has taken at minimum seven days to arrive. For those of you having fitment issues, the customer service at gmr is top notch. Got it installed and function checked on bench. Ready to try it at my range. Thanks again and look forward to ordering the next one for another build soon.

  • 5
    Kit R

    Posted by Matt on Mar 13th 2026

    The product is great, especially for the price. I own an original drop in FRT from another brand and this works just as good at less than 1/3 of the price. Installation is easy with simple tools that any AR owner SHOULD already have. I'm very happy with my purchase. ** Side note: the stickers that I received with my kit are A+ 100!!!

  • 5
    Installed dozens

    Posted by David on Feb 19th 2026

    As a Gunsmith I see all the problems, These SS's are top shelf. Once installed I never see them again I stopped installing "gun show specials" Etc. as they are riddled with problems. If my customer wants to provide his own SS he gets it from GMR.

  • 5
    Good communication

    Posted by Collin on Dec 22nd 2025

    I had some problems at the beginning with 2-5 rounds being fired then a light strike connected the seller and he responded same day and helped me figure out the problem was not the safety and it was prior user from buying a used pew .

  • 5
    4140 ss

    Posted by jeremiah strickland on Oct 13th 2025

    Yeah I’m about to order another one!! That’s all that need to be said.

  • 5
    GTG

    Posted by Dustin on Sep 19th 2025

    Super easy to install in my AR9. Works excellent !

  • 5
    Great stuff

    Posted by Drake on Sep 16th 2025

    Delivered fast, product is good. So good im going to keep buying as many as I can and whatever else gmr puts out.

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