Allen Engineering Mk12 SPR collar and adapter

Ops, Inc. #12 model - short collar original model

Perfect replacement for Ops Inc. #12, fits AES-5.  This is for the Mk12 clone build, as well any other great rifle build. 

This is made to fit the tight space on a Mod 0 rifle, given the larger platform PRI flip-up gas block.  This is the original short collar version.  This can be used on any build, but the long collar is best for a Mod 1 build

Ron Allen builds these one by one by hand.  He was the engineer that created the Ops Inc. collar and suppressor.  Well worth the money for any precision 5.56 mm rifle build.  Ron created the collar while working at Ops Inc.  This is the exact same collar.  If someone wants to argue otherwise, you might find something where a roll pin is .001" in a different spot, but I have not found it.

This is 100% genuine Allen Engineering.  There are a lot of companies making knock-off "Ops Inc" collars.  Even some rifle manufactures building very nice Mk12 rifles with the wrong brake and collar.  If you are not going to run a can, the knock-off or generic Ops Inc might work fine.  But for the small price to get the real deal, we do not work with, nor endorse any other manufacturer.  The tolerances to get the profile, collar, the threads, all in the right spot to align the suppressor are very tight, and Ron tells us he is seeing baffle strikes on his cans caused by another manufacturer's collar and brake, or a poorly executed SPR profile on the barrel.

Included is the complete kit:  Collar, flash hider, thread protector and shim kit.

One picture shows the comparison between long and short collars.