... Medium: R134a, R22, R407C, R404A/507, Water and oil 3) Material: Brass Oil Flow Switch FSF series :FSF20W- 3/4 Magnetic flow ... switch has lots of advantage, such as simple usage, small bulk, light weight, sensitive and reliable action, and etc.Technical ... : 1AAvailable medium: R134a, R22, R407C, R404A/R507, oil and mixture of oil and refrigerant. Type data ModelConnection size(inch)Flow rate ...