In the summer 1942, the Askania company began work on the EZ 42, a gunsight which could be adjusted for the target's wingspan (in order to estimate distance to the target). Three examples of the first series of 33 pieces were delivered in July 1944. These were followed by further 770 units, the last being delivered by the beginning of March 1945. Each unit took 130 labour hours to produce. The EZ 42 was made up by two major parts, and lead computation was provided by two gyroscopes. The system, weighing 13.6 kg (30 lb) complete, of which the reflector sight was 3.2 kg, was ordered into mass production at the Steinheil company in Munich. Approximately 200 of the sights were installed into Fw 190 and Me 262 fighters for field testing. The pilots reported that attacks from 20 degrees deflection were possible, and that although the maximum range of the EZ 42 was stated as approximately 1,000 meters, several enemy aircraft were shot down from a combat distance of 1,500 meters.