12 volt Double Contact Make/Break Relay.
Isolates fridge circuit separately.
Splits alternator charge between starter battery and leisure battery.
The extra terminal isolates the fridge circuit.
2 x 2.8mm, 1 x 6.3mm and 2 x 9.5mm terminals.
Replaces Lucas SRB 630 (fitted to many older camper vans and motor homes).