Gear Wheel Flow Meter series DZR have been designed for a cost effective flow measurement for viscous fluids. The measuring unit consists of a pair of gear wheels which is moved by the flow according to the principle of gear wheel motor. The bearings are – according to the material combination – either ball bearings or gliding bearings. The dif-ferent versions vary through different housing materials, lubri-cation properties, through the medium being used and the accuracy.