THE DEVICE MANUFACTURING LLC. - Mk3 Device "Lite" AR-15 Upper Receiver Fixture

I’ve had mine since November 2024. From then to now, it has proven to be indispensable. I have Tremors so first and foremost it keeps both of my hands-free so that I can be more steady with assembly and disassembly of my Ar’s. I have the old Sig 516, the MCX lite in 300 blackout, the MCX light in 556, the LWRCI in 556, and a Faxon Fire Arm's AR-15 in 556 also. It holds each one firmly and securely in my vice, so that I can maintain, change hand guards, add new sites, and I’m always changing my scopes around I also have Two BRN-4’s w/10.4 inch Heavy Barrell’s. I installed Midwest Industries Quad rails w/no problem’s. I would recommend this Jig to Anyone! It is a very stable Platform,to work off of. Some of Your cheaper Ar’s may vary internally, but most fit’s very well. I’m glad that Brownells carries this tool because I plan on buying at least one more. I hope that this review helps those of you that might be on the fence thinking about buying this product. It doesn’t take up much room in your tool box, and if you wanna leave your upper on this jig, you can always come back to it whenever it is convenient, and don’t forget about the slot on the bottom that helps you configure your M lock accessories. Well, I hope this has been a help to anyone interested in this product. It has sure helped this old man with arthritis and tremor’s. I can’t work very long without having to rest so it’s nice being able to leave your work in place so that you can come back to it. Well, thanks guys and gals, if any of you find any more nice tools like this, please let me know, I’m always willing to give them a try. Your friend Tom

This fixture is very easy to ise and works great! I would recommend!

Absolutely the best receiver vice ever made. Bombproof sturdy. And no marring of your receiver for heavier poundage torque. This will be the last receiver vice you’ll ever buy.

As SB noted in a previous review this tool WILL NOT fit an Aero upper without damaging it. I tried fitting my Aero M4E1 upper onto this tool and as soon as the BCG brace hits the T rail inside "The Device" which holds the whole thing together it jams right there. I had to CAREFULLY tap the BCG brace back out. Maybe this will be fine for some uppers definitely not an Aero M4E1.

This tool is worthless. The portion of the device that mimics the BCG will not fit into a Aero AR 15 stripper upper receiver. There is so much friction between the internal portion of the receiver and the tool that it prevents seating the tool completely. Even lubrication would not help. The fit is too tight. Using this tool as designed would result in damaging your upper receiver.