The Heckler & Koch MP5 is a 9mm submachine gun of German design, developed in the 1960s by a team of engineers from the German small arms manufacturer Heckler & Koch GmbH (H&K) of Oberndorf am Neckar. There are over 100 variants of the MP5, including some semi-automatic versions.
The MP5A3 is the most popular version of the MP5, and features the SEF trigger group and a retractable stock.
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