... flow switch is mainly used to monitor and control the flow of the medium in pipes.FSF series ... , etc.FSF series oil flow switch has lots of advantage, such as simple usage, small bulk, light ... R134a, R22, R407C, R404A/R507, oil and mixture of oil and refrigerant. Type dataModelConnection size(inch)Flow rate ... /4 ODF148FSF1W1 ODF194 Oil Flow Switch monitor and control the flow of the medium in pipes