Abstract: A universal joint comprising a pair of coupling devices each including a generally cylindrical portion having an extension at one end including a plurality of projections which are outwardly divergent and circularly spaced. Such projections of each coupling device are arranged to have their successively adjacent side surfaces formed to define therebetween spaces the bounding sides of which are divergent. In the assembled relation of the coupling devices the projections of the respective extensions thereof are relatively rotatively displaced and interfit and the projections of one thereof are respectively projected in, through and beyond the spaces defined between the bounding sides of the projections of the other of said extensions.