MCX/MPX AR-15 Stock Adapter

Stock adapter for using Sig style MPX/MCX folding stocks and braces on our 10/22 Chassis or AR-15’s with a 22LR conversion.

Billet 6061 T6 Aluminum Black Type III Hardcoat Anodizing.

*Gun and stock are not included

*Does not work with standard Semi-auto AR-15 recoil system.

Works with Sig MCX and Brownells BRN-180 uppers, Sig P556 pistols and Kriss Vector pistols as well as many others.

Engineered Silence to become Adder Arms

We are excited to announce our renaming and rebranding effort. Engineered Silence is in the process of becoming Adder Arms. Expect innovative new products along with a new website in Q1 of 2021. Don’t worry. Your favorite ES products will live on under the Adder Arms name. In fact, some of the products that you order now will come branded as Adder Arms. These items are otherwise identical to the ES products shown.