MP5K

The MP5K was a weapon cut from both Grand Theft Auto: Vice City and Grand Theft Auto: San Andreas. In Vice City, it exists under the name of mpfshrt and is also seen being used by Diaz' goons in In The Beginning.... The GTA San Andreas rendition appears only in the files, in the gta_int.img. It has a dirt texture though, much like the M16 seen in Stowaway. In the same mission, there are unique crates with an MP5K picture on it.

Very little is known about the weapon, and is unknown why it was cut from both games. However, it was an earlier feature before the actual MP5 replaces it. This makes sense, as the real-life MP5K is a shortened version of the original MP5 (specifically, the MP5A2).

Trivia

 * In Grand Theft Auto: Liberty City Stories, the SMG loosely resembles the MP5K.
 * In both GTA Vice City and GTA San Andreas, an MP5K can be seen among weapons on the shelves/racks inside Ammu-Nation but it can't be purchased in either game. This is not the case in The Definitive Edition, where the displayed weapons are different.
 * Additionally, The Definitive Edition replaces the MP5K by a Tec-9 during In The Beginning...