The KNS Stock Adapter with Flange (brand part no. AR-MCX Adapter with Flange) converts an AR-15’s buffer tube interface to a Picatinny rail mount, letting owners run a Picatinny-style stock or brace, such as the SIG MPX folding stock or brace, in place of a traditional AR buffer tube. It’s built for buffer-less systems that require a takedown pin spring or detent, and it’s machined from steel for a durable, precision fit. This adapter is designed to fit AR-15 platforms without a buffer installed, giving builders a clean way to run non-standard, Picatinny-interface stock and brace options.

Key Specifications

• It converts the AR buffer interface to a Picatinny rail mount.
• It’s built for buffer-less systems that require a takedown pin spring or detent.
• It’s machined from steel for a durable, precision fit.
• It allows mounting of a Picatinny-style stock or brace, such as the SIG MPX folding stock.
• It’s built to fit an AR-15 without a buffer installed.

Frequently Asked Questions

What does this adapter let me install? It lets you mount a Picatinny-style stock or brace, such as the SIG MPX folding stock, in place of a standard AR buffer tube.

Does this require a buffer to be installed? No, it’s built for buffer-less systems that use a takedown pin spring or detent instead.

Buy the KNS Stock Adapter with Flange

Run a Picatinny-interface stock or brace with the KNS Stock Adapter with Flange. Shop more KNS Precision AR buffer system parts and get fast shipping from our Lubbock, Texas gun shop.