The Flow Rate Sensor allows you to easily measure stream velocity for environmental or earth science studies. Students can measure the flow of a stream at different points in m/s or ft/s. The impeller rod separates into four sections for easy transport and convenient storage. The Flow Rate Sensor comes with a five-meter cable so your data collection equipment can stay on shore while you measure flow rate in a stream. Three riser rods which enable the impeller to be placed at fixed depths, are also included. Analog sensor.