The Standschütze Hellriegel 1915, was a submachine gun chambered for 9mm Steyr rounds. Contrary to popular belief, the weapon is not belt-fed; the magazine was connected to the weapon by means of a flexible connector, which gave the weapon the appearance of being belt-fed. The drum was spring-tensioned, and the weapon can also use stick magazines. The barrel was fitted with a water cooling jacket. Although the term "submachine gun" had not yet been coined in 1915, the Standschütze Hellriegel is an example of a "heavy submachine gun".