SIG Sauer MPX Copperhead K 9mm Luger Micro Pistol, 4.5 in Barrel, Timney Single-Stage Trigger, SIG Side-Folding Brace, 20+1 Capacity, 3‑Lug Muzzle
This MPX Copperhead K stands out as a compact, gas-piston 9mm with a quality aftermarket Timney single-stage, flat-faced trigger already installed. It features the MPX monolithic upper with a continuous 12 o'clock Picatinny rail, a visible 3-lug muzzle interface with a knurled collar, and a side-folding single-strut SIG-marked brace. Two 20-round SIG MPX factory magazines are included.
Condition
Overall Condition: Good condition, showing some signs of prior use and handling.
Bore Overall Condition: Good - Clean, well-maintained, minor wear marks.
Bore Rifling: Good Rifling - Intact, well-defined lands and grooves.
Specific Condition Notes: Handguard has visible scratches on the left side. Exterior shows scattered scratches and small blemishes. Bore presents a bright, shiny interior.
What’s Included
- 2x 20-round SIG MPX factory magazines
- SIG side-folding pistol stabilizing brace (installed)
- Flat-faced trigger shoe (installed)
- M-LOK Picatinny accessory rail section (installed on handguard)
The MPX Copperhead K uses a semi-automatic, short-stroke gas piston system with a closed/locked rotating bolt. This operating system is at the core of the MPX design and is paired here with the micro-format Copperhead K configuration and a 4.5 in barrel.
The upper is the MPX monolithic design with a continuous 12 o'clock Picatinny rail, providing a solid top rail section. Controls are modern and accessible: ambidextrous magazine release and ambidextrous safety selector, plus a left-side bolt catch and right-side bolt release.
Up front, the short aluminum M-LOK handguard keeps the footprint compact and includes an installed M-LOK Picatinny accessory section. The muzzle shows a visible 3-lug interface with a knurled collar. At the rear, the single-strut SIG-marked brace folds to the side for stowage and transport.
This example is customized with an aftermarket Timney single-stage, flat-faced trigger, delivering a crisp, consistent pull. Capacity is 20+1 with the included 20-round factory magazines. The aluminum alloy receiver and frame keep weight down, and the pistol is made in the USA.