The series consists of a N (Normal) version complying to ISO 1724, which is generally used for standard applications, and a S (Supplementary) version complying to ISO 3732 to be used for additional connections. The S version can easily be recognized by its white coloring and by the different order of the contacts, thus preventing an incorrect connection to the N version. Littelfuse supplies these connectors in aluminum body with screw and flat contacts. Included in the series of sockets are also special versions with rear fog light (00437200) and 16 rear flat terminals (5 double and 2 triple 00435700) to double electrical system on the trailer, avoiding the use of junction boxes. Standards: Conforms to ISO 1724 & ISO 3732 recommendations and standards Accepts all 7-pole plugs that conform to ISO 1724 & ISO 3732 Screw terminals versions are mainly intended for the replacement aftermarket Flat terminals versions are generally preferred by harness manufacturers.