This is the Grimeca 105 mm hub that was fitted to many MCB models 1966 - 72
MCB purchased hubs from Italian Grimeca 1966-72. In 1972 the hubs were gradually replaced with hubs from Leleu.
To identify the Grimerca 105 mm, the following dimensions are needed : The inner diameter of the brake drum is 105 mm, the outer diameter of the bearing shells is 32 mm and the wheel axles are M12x1