Sig Sauer Mpx/Mcx M4 Style Folding Stock Black

The Sig Sauer M4 style folding stock for MPX/MCX platforms gives you a compact, stowable platform without sacrificing ergonomics or control. Whether you're running a short-barreled rifle in tight spaces, moving through vehicles, or just want a more packable setup, this factory Sig stock folds away when you don't need it and deploys quickly when you do. Built to Sig's specs and engineered for their piston-driven 9mm and intermediate caliber systems, it's a straightforward upgrade from the factory configuration.

Installation is straightforward—the stock interfaces with your MCX or MPX receiver via standard 1913 Picatinny mounting, so if your platform is already set up for that interface, you're ready to install. The folding design lets you transition from a full-length, shootable length-of-pull to a dramatically shorter profile for storage, transport, or tight-quarters movement. Black finish keeps it consistent with typical MCX/MPX uppers and components.

This is a genuine Sig Sauer part, not an aftermarket adapter or universal stock forced onto your receiver. That means fit, function, and feel are dialed in specifically for the MCX/MPX platform. If you've run Sig's piston guns and know they need a stock that matches their build quality and performance promise, this is it.

Key Features

• Folding design reduces overall footprint for transport and storage
• Factory Sig Sauer engineering for MCX and MPX platforms
• 1913 Picatinny interface for secure, repeatable mounting
• Black finish

Specifications

Frequently Asked Questions

Will this stock work on my MPX or MCX?

Yes. This is a factory Sig Sauer stock designed for both MPX and MCX platforms that feature the 1913 Picatinny receiver interface. Verify your receiver has the 1913 mounting surface before ordering.

What's the difference between this and a universal folding stock?

This is a factory Sig part engineered specifically for the MPX and MCX systems. Universal stocks may work, but Sig's design is tuned for receiver geometry, recoil impulse, and controls layout on these platforms.

How does the folding mechanism work?

The stock folds down when not in use, compressing the footprint of your rifle. When you need to shoot, it deploys into full length-of-pull position, secured by the 1913 interface. The exact operation depends on the stock's internal latch design; consult the manual included with your stock for detailed deployment steps.