Renold Hi-Tec rubber-in-compression couplings are preventing shock loading and torque overload on a new reduction gearbox installation at a Swiss slab mill. A torque limiting device was fitted to a PM60 rubber-in-compression coupling on the new gearbox's input shaft. The output side of the gearbox operates at 27rpm and generates torque of 31kNm. Here a PM850 coupling was used with a spacer to bridge the gap between the gearbox and the slab mill. The couplings have significantly reduced shock loads on the gearbox by minimising torque amplification and absorbing vibration energy. Apart from reliability improvements, the plant now runs more quietly due to the fact that there is no metal-to-metal contact in the rubber-in-compression coupling design.