The 8 cm Luftminenwerfer M 15 (Pneumatic trench mortar) was a light mortar used by Austria-Hungary in World War I. It was designed by the 58th Infantry Division and the first twenty were built in the division's workshops. Later production was contracted out to Vereinigte Elektrische Maschinen A. G. in Budapest. It used the breakable screw method to retain the bomb in place until the air pressure in the chamber was strong enough to break the screw. Grooves of different depths could be used to vary the range. It was sometimes referred to as the Roka-Halasz system.