The Turm III or Erprobungsträger mit 3-achs-stabilisiertem Turm (Testbed with 3-axis stabilized turret) was a West German prototype tank built to test a 3 axis stabilizer system. So far stabilizers had only gone in 2 axis, Vertical stabilisation and horizontal stabilisation, but the Germans wanted to test the 3rd axis, Roll stabilisation. It was also thought to improve accuracy of the gun since when a tank is on the side of a hill the sight will be more of an X instead of an +.

Altough the project was cancelled due to the complexety and cost, there still was testing done on the Marder IFV with a similar 3 axis stabilizer