Greyline Instruments PDFM 4.0 Portable Doppler Flow Meter PDFM 4

With its 4-20mA output you can even use the PDFM 4.0 as a spare transmitter in critical applications. For flow studies and troubleshooting use the built-in 50,000 point Data Logger. The PDFM 4.0 is fast and easy to operate - you can mount the sensor on the outside a pipe in less than a minute.

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