The MP5K is a submachine gun that appears in Call of Duty Black Ops
The MP5K appears in the mission "Executive Order". The on Mason wields has Extended Mags and a Red Dot Sight attached while Woods wields one without any attachments.
The MP5K has the slowest reload timess of all SMG, but also ties with the AK-74u for the highest damaging SMG. Compared to its Modern Warfare 2 counterpart, it's largely the same except for a lower recoil.