This model OCF 5.0 open channel flow monitor uses a non-contacting ultrasonic sensor to measure wastewater flow through flumes or weirs. It features a powerful, built-in data logger with on-screen flow reports and output to USB flash drives plus. Calibration and selection of flume or weir are made through the built-in five-button keypad and user-friendly menu system. Temperature compensation is automatic and accuracy is ±0.25%.