Koolance ADT-FM03 Flow Meter Frequency Adapter The Koolance Frequency Adapter multiplies INS-FM16, INS-FM17N, INS-FM18, or INS-FM19 flow meter RPM signals to allow readability by most fan tachometer headers. A small green power LED on the unit blinks according to flow meter rotation rate. The flow meter RPM reading is intended to allow fan detection software (including BIOS) to enable the appropriate alarm or shutdown procedure if the flow meter impeller stops rotating. The "RPMs" represent approximate coolant flow rate in mL/min and not the flow meter's revolutions. For accuracy, set the ID switch to either 10/13 (for 10mm or 13mm ID) or 6mm depending on your tubing internal diameter.