Colt M4/AR15 4-Position Receiver Extension
Great experience buying this. I'm going to buy another.
Great fit and finish.
If your building a new build or replacing an old existing part, look no further, this is what you need.
Quality part; fit and finish is perfect. Colt's has the notches for proper staking of the end plate. As always, great AU service!
My Colt castle nut was shipped fast and is typical Colt quality. AU is my go to for Colt products.
High quality mil-spec part. A.U. Great company.
I needed an extra castle nut, preferably Colt brand, and Arms Unlimited had it at the best price, with free shipping to boot.
Always top notch parts, AU always efficient with fast service.