The SF4-D-24 is a 8-pole polarized, monostable Safety Relay with forcibly guided contacts. 4NO-4NC contact configuration, AgSnO2 with Au flash contact. Relay complies with EN 50205, Type B. Overvoltage category as per IEC 60664-1 III/4kV. Rated voltage as per IEC 60664-1 basic insulation.