The MP5K (K from the German word Kurz = "short") was designed for close quarters battle use by clandestine operations and special services. The MP5K does not have a shoulder stock (the receiver end was covered with a flat end cap and the bolt and receiver were shortened at the rear.

The Tokyo Marui MP5K High Cycle Series looks no different than the tried and true standard series MP5K, however its internals have been given a complete make-over by Marui. Featuring a hand made ultrahigh-speed rotation motor thats achieves 30,000 revolutions per minute, and a High Cycle Mecha-Box coupled with Top of the Line Japanese bearings.