Seilzuganlenkung ohne Stahlse Graupner 7815.20.0 For a slop-free linkage to a control surface. The combination of ring-screws and clevises provides a straightforward method of adjustment for the two control cables after installation. A pair of pull-pull (closed-loop) cables, which are often used for control surfaces such as the rudder, weighs only a fraction of a steel pushrod.