Tenders for Supply of Relay Ac Immune, Style Qta-2 Dc Neutral Track, 09 Ohm, 4F/2B Contacts Front And Back Contacts Metal To Carbon, Complete With Plug - Board Retaining Clip And Connectors Confirming To Brs :939A, Brs - 966 Appendix F2 Irs:S-34 And Irs:S-23As Applicable. The Interlocking Code For This Unit Shall Be Fghkx.