The round rubber Saga universal joints have a spherical ball and socket, made of steel, in the center of the “Donut”. Because of the structure of the metal frame it is not possible to lubricate this ball and socket without some special equipment. This short steel extension was provided in some of the late tool bags. It is not shown in the 250 tool bag photos or drawings but it is necessary for these cars. I suppose that a factory-trained mechanic would have this tool and would be the person doing this type of work. This tool is 60mm long and has 8×1 threads at each end. U-Joint Grease Extension.