FLOW METER EU-108W  Ultrasonic Flow Meter is a fixed mounted flow meter, the flowmeter is separated with the transducer. Their electronic enclosures are rated as IP65 (NEMA 4X), so this products could be installed for both indoor and outdoor, then there will be no limited for the installed place. CE certificate. The ultrasonic flow meter works with Ultrasonic Technology and Measures by Principle of time difference. There is a pair of ultrasonic vibrator and receiver in the exterior of pipe emitting in two directions and both face to face. The light vibrator will emit ultrasonic signals down stream and reversed stream. Measuring the time difference of the two directions transmission, you will get the flow rate of the fluid; then input the diameter of pipe, you will get the flow. Specification Linearity - 0.42% Repeatability - 0.17% Accuracy - Normally -/+0.8% of reading at rates>0.2mps Response Time - 0-999 seconds, user-configurable Pipe Size - 1/2" ~ 240" (DN15mm - DN6,000mm)* Pipe Material - All metals, most plastics, lined pipes Units - English (U.S.) or metric Liquid Types - Virtually all liquids and liquids with minor solids (<10,000ppm). Full pipes Digital Interface - Relay/OCT/RS-485/4~20mA/ 0~20mA output. Power Supply - 220V AC /  24VDC / 85~264VAC