Ferrari used these button-type grease fittings from the very earliest cars until the 275’s. During the production of the 250 series cars some of the pieces purchased from outside suppliers used the normal snap-on type. The sealed tie rod ends are a good example showing that a lot of the later cars used both types of grease fittings. The button type grease fittings were made of brass and plated with a very thin layer of nickel. The nickel finish quickly wore off due to dust and dirt on the road plus the factory recommended 2,500 mile lubrication schedule. The button type grease fittings all used the same dimension for the shaft and head but there was a variety of thread sizes. 8x1mm: this is the most common size of the 250 series cars.