The SIG Sauer MPX K is a compact 9mm semi-automatic pistol built around a closed-bolt gas-piston operating system. Its 4.50-inch carbon steel barrel has a Black Nitride finish and a 13.5x1 threaded muzzle for suppressor-compatible setups. The platform combines an aluminum receiver with a modern M-LOK handguard, full-length Picatinny rail, SIG PCB folding pivoting contour brace, and black polymer grip. A Timney single-stage trigger provides a crisp control interface, while the ambidextrous safety and controls support flexible handling. The pistol accepts 35-round magazines and measures 22.25 inches overall.

Key features

• Closed-bolt gas-piston system supports reliable cycling and clean, consistent operation.
• 4.50-inch Black Nitride carbon steel barrel with 13.5x1 threads is configured for suppressor use.
• SIG PCB folding pivoting contour brace provides compact storage and supported shooting control.
• M-LOK handguard and Picatinny receiver rail support accessory and optic installation.
• Timney single-stage trigger delivers a crisp, predictable trigger pull.
• Ambidextrous controls and safety accommodate right- and left-handed users.

The SIG Sauer MPX K combines compact dimensions, modular accessory mounting, and dependable 9mm performance in a folding-brace pistol platform.