This is a TRW Clutch Master Cylinder for a Triumph 1968 TR250 and Triumph 1969 TR6 with 0.75" bore size. The cylinder will work for all years of Triumph TR6's and will bolt on with no modifications. Compared to the later Triumph TR6 with the .70 bore this cylinder will give you about 15% more throw in the clutch. TRW has changed the mold on their cylinders so the units no longer carry the Girling cast into the side of the cylinder. Also the metal cap has been replaced with a plastic cap, but the metal caps are able to screw onto the cylinder.