As with all MPX, the K is modular allowing for multiple handguard and barrel lengths and is ready to go for suppressor use. For 2019, the K now features the SIG PCB folding brace which allows the K to fold into an ultra-compact size and be operable in the folded position. The K also features an updated M-Lok handguard which is available as accessories in multiple lengths for suppressor coverage. Finally, the K is upgraded with the ultra smooth, ultra-fast Timney Trigger. Co-designed by Timney and SIG, this trigger offers the Timney performance you have come to expect we with the ultimate reliability to make it survive the punishment of a sub gun platform. If you are looking for the ultimate modular sub gun, look no further than the MPX K from SIG SAUER. Comes with a 4.5″ barrel and ships with one 30rnd magazine.