This is a TRW Brake and Clutch Master Cylinder Kit for a Dual Brake Master Cylinder for a MGA 1500, 1600, MKII, (Not Twin Cam)  Triumph TR2, TR3 to TS13045,Austin Healey Sprite 1958 to 1962 (948cc Engine) and MG Midget 1961 to 1962 (948cc Engine).   A Quality made kit that comes with a new top gasket to complete your master cylinder rebuild.