A flexible jaw coupling is a positive, torsionally flexible coupling which also permits radial, axial and angular displacements between the driving and driven parts. It is failsafe. Two coupling halves with concave claws are located opposite each other, offset circumferentially by half a pitch division. An involute elastomeric with crowned tooth profile is located in the space between the claws. The spider insert is extremely wear resistant, to oil, ozone and ageing, and notable for its resistance to tropical conditions. The high internal damping protects the drive motor from dynamic overload. At an operating temperature of -30 °C to +80 °C (-22 °F to +175 °F) [including short term temperature peaks  up to +120 °C (248 °F)], perfect operation is guaranteed. The progressively rising spring characteristic ensures that vibration energy is rapidly reduced and limits the vibration amplitude. In contrast to other flexible couplings, the elastomeric teeth of the spider insert are not subjected to bending stresses, but only to pressure, thus resulting in lower wear and a higher load capacity for the teeth. Manufacturing of the couplings from high quality precision castings reduces imbalance and has a positive influence on running characteristics and service life. Flexible jaw coupling can be installed both horizontally and vertically. The specially machined surfaces facilitate rapid and reliable alignment of the coupling on installation.