... -C,TT,IT 3.Rated voltage:380V SP2 SPD,Surge Protective DevicePor Surge (Power Suppressor,Surge Protective,Surge ,Lightning,Arrester,spdSurge Protective Device,SPD,Surge Arrester,surge protection,surge ... .Apply to the power supply such as TN-S,TN-C,TT,IT 3.Rated voltage:380V Surge Protective Device MQU9-C 4P SPD