SIG Sauer MPX K Pistol 9mm, 4.5 in Threaded Barrel, No Brace, Ambi Controls, M-LOK, Matte Black
This SIG Sauer MPX K Pistol is a compact 9mm configuration with a 4.5 in threaded barrel and no-brace setup, built around the MPX short-stroke gas piston system. It features a monolithic-style aluminum upper with a full-length Picatinny top rail, an aluminum M-LOK handguard, and fully ambidextrous controls. The factory carton label (SKU PMPX-4B-9-NB) was observed with a date of February 21, 2023 and matches the firearm.
The pistol includes an open-prong flash hider, a flat-faced single-stage trigger, an ambidextrous charging handle with extended latches, and an AR-style left-side bolt catch. The receiver is marked "SIG MPX • MULTI-CAL." and the finish is matte black throughout. No iron sights are installed. One 30-round SIG MPX-pattern polymer magazine is included.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Overall Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Details: Minor scratches and blemishes are present.
What’s Included
- SIG Sauer factory cardboard box with matching label (SKU PMPX-4B-9-NB)
- SIG Sauer safety/operation paperwork (QR-code card for operator's manual/registration)
- 1x 30-round SIG MPX-pattern polymer magazine
The MPX K Pistol format delivers a short 4.5 in steel barrel with factory threading and an open-prong flash hider, offering a compact footprint while maintaining the MPX operating system. The no-brace configuration keeps the rear of the receiver clean while retaining the integral 1913 Picatinny end-cap interface for a stock or brace if desired (none included).
Its monolithic-style aluminum upper pairs with a compact aluminum M-LOK handguard and a full-length Picatinny top rail. The pistol ships without iron sights, giving a clean top rail for the user to configure as needed.
Controls are fully ambidextrous, including the safety selector and magazine release, with an AR-style left-side bolt catch. The ambidextrous charging handle features extended latches for positive manipulation, and the flat-faced single-stage trigger provides a straight press. The SIG polymer pistol grip includes molded texturing.
The aluminum receiver and frame wear a matte black finish for a consistent, professional appearance. Capacity is 30+1 with the included 30-round magazine. Receiver markings read "SIG MPX • MULTI-CAL." and the country of origin is the United States. The factory carton label observed is dated February 21, 2023 and matches this configuration and SKU.