The first three batches were equipped with the Benz Bz.III engine. The last two batches, 35 aircraft in total, were equipped with the Maybach Mb.III engine. The first four batches were armed with one fixed Spandau machine gun, mounted on the starboard side of the nose. The final batch of 20 aircraft, delivered between October 1917 and February 1918, were armed with twin Spandau machine guns on either side of the cockpit. Production was slow, so that many were obsolete almost as soon as they reached their units. They were difficult to fly because of the aforementioned poor directional stability. Recovery from a spin was a matter of luck. Another reason it was unpopular with pilots was that, until the final batch, the armament was positioned out of their reach, making it impossible to clear stoppages while airborne.