MPX-K (Compact variant) A compact variant with a 114 mm (4.5 inch) barrel. MPX (Standard variant) A pistol variant with a three-position collapsible arm support with a stock like appearance, three-position fire selector if it supports full automatic and an 14” blind pined and welded muzzle brash 16”, 8.0, 6.0 4.5 inch barrel.

This model has a 4.5' threaded barrel, black hard coat anodized metal finish, and a short aluminum KeyMod handguard with handstop. A full-length picatinny rail allows for solid, consistent mounting of optics and targeting lasers. Shockwave Sierra Bullets Sig Sauer Sightmark. Bersa Bianchi Birchwood Casey Black Aces Tactical Black Hills.