Running Contract for supply of Relay, plug in type, Style QL1, DC magnetically latched neutral line, 24 V DC 11F, 4B contacts, front and back contacts metal to carbon, with plug board, retaining clip and connectors conforming to BRS: 935A, IRS: S 34 & IRS: S 23 ( as applicable ). The interlocking code for this unit shall be ABDEG.