interchangeable expansion valve 1.For R22,R134A,R407A,R507/404A 2. easy to change driving head and valve disc 3. ... to customers requirement.l Suitable for R22, R134a, R407C, R507/404A.l If you have special requirement,please cantact STF.Superheat ... .3°C. interchangeable expansion valve, for R22,R134A,R407A,R507/404A(TCL/TRF)