This is a wheel cylinder for Triumph TR3 from TS34404 to TS56376, TR4 from CT5656 (wire wheels), CT5783 (disc wheels), TR4A, TR250, TR6 with a .70 bore and Slotted Piston. Can be used for the TR3 from TS34404 to TS56376 that originally had the 5/8 cylinders, .70 is the closest bore size. Made in Italy by AP Braking Cross Reference 580-045, 64674185, 7-953.