The KOBOLD OME positive-displacement flow meter incorporates proven helical gear, also known as worm gear or screw gear, technology. The flow meter provides the quiet, non-pulsating and low pressure-loss operation for which helical gears are renowned. The OME is designed to be used only with non-abrasive, lubricating liquids. The precision and reliability of the device is equivalent to our top-of-the-line spur gear flow meters. No performance sacrifices have been made. The rotation of the helical gears is detected by one, externally-mounted proximity sensor. This makes the addition of a second sensor for redundancy, frequency multiplication or directional sensing possible at little additional cost.