Panzer III addition, to counter enemy anti-tank rifles, starting from 1943, the Ausf. L version began the use of spaced armour sideskirts and screens (known as "Schürzen" in German) around the turret and on the vulnerable hull-sides. However, due to the introduction of the upgunned and more-armoured Panzer IV, the Panzer III was, after the German defeat at the Battle of Kursk in the summer of 1943, relegated to secondary/minor combat roles, such as tank-training, and it was finally replaced as the main German medium tank by the Panzer IV and the Panzer V Panther. The Panzer III's strong, reliable and durable
GL Mk. III radar prone, and a radar system could dramatically improve this task. The development team, nicknamed the "Army Cell", was set the task of building a system that would provide slant range measurements with an accuracy of or better. The result was an unwieldy system known as the GL Mk. I radar. The Mk. I, like the Chain Home technology it was based on, used separate transmitter and receiver antennas that had to be moved in unison to track targets. The system did not provide an accurate bearing measurement, and had no provision for measuring elevation. It did, however, meet the requirement