9 inch girling mount, 17.5mm piston diameter.
TR3A from serial number TS34404 to number TS56376
TR3B "TCF serie"
TR4 from number CT4388
TR5 from 1967 to 1968
TR6 from 1968 to 1976
Can be used to replace the original reference 119600 (which is no longer manufactured) in diameter - 0.625".