Thermostat Capillary adaptor for DB2/4 MkII & MkIII thermostat housings, can be soldered into radiator if required for DB2 & DB2/4 Mk1, better still is to use our thermostat housing as what do you want to know the pemp of the radiator for, its too late if that reaches 100°c, the engine has a head gasket failure at the best or a cracked head at worse case