Pressure Switch 1.Reset method: auto reset, manual reset 2.Fitting structure: copper tube welding, copper flare fitting ... .Type descriptions (types classified by):1. Reset method: auto reset, manual reset2. Pressure range: extra-high (800 ~ 2,200PSI), high (145 ... +/-15+/-15MPS350High Pressure350- -+/-15+/-15MPS450Manual Reset450- -+/-15+/-15 heat pump electronic water pressure control switch