Redesigned 2019. 9x19. Closed bolt gas piston system, modular design allows for multiple handguard and barrel lengths and is ready to go for suppressor use. For 2019, the K featured the SIG PCB folding brace and an updated M-Lok handguard and a Timney MPX Single Stage Trigger co-designed by Timney and SIG. OAL, 22.25"; overall width, 2.4"; height 8"; 4.5" barrel, 1:10 twist; 5 lbs. MPX magazine type.