UL-320 is a clamp on type ultrasonic flow meter. The ultrasonic sensor is mounted to exterior of existing pipe by clamping so that it does not come into contact with fulid flowing thereby making it safe for use in measuring corrosive and hazardous fluids flow rates. Fluids with suspended particles, metallic ions or even small air bubbles can be monitored with use of DSP and AD converters which speed up measurement parameters and have proven record of bubble resistance. Lack of moving parts guarantees smooth long life. The UL-320 can be conveniently used irrespective of pressure of fluid and has options to indicate forward/backward flow rate, total flow, pulse data and alarm output. Combination with RS485 serial output provides flow controlling capability.