The MP5A4 is the 3-round burst variant of the MP5A2, featuring a fixed stock and a modified trigger group that allows semi-automatic, 3-round burst, and full-auto fire. The 3-round burst capability was developed in response to military doctrine emphasizing controlled fire. Less common than the A2 and A3. Type: Submachine Gun Action: Roller-Delayed Blowback Caliber: 9mm Capacity: 30 Year introduced: 1976, Germany Weight: 5.7 oz Overall length: 26.77" Status: Active Military use: Yes Intended use: Military Use, Special Operations