FSF series Oil Flow Switch : 1) Connection: 3/4"ODF 2) Medium: R134a, R22, R407C, R404A/507, Water and oil 3) Material: Brass FSF ... series Oil Flow Switch :FSF20W- 3/4 Magnetic flow switch is mainly used ... : 1AAvailable medium: R134a, R22, R407C, R404A/R507, oil and mixture of oil and refrigerant. Type data ModelConnection size(inch)Flow rate ...