Abstract: It is known to provide studs having externally screw-threaded spigots which are screwed into sockets provided in the soles of articles of footwear. In use, lateral forces applied to the ground-engaging portion of such a stud tend to damage the associated socket, particularly if the socket is made of a plastics material. To resist radially outward expansion of the socket the invention provides retaining means spaced outwards from the spigot. The retaining means may consist of a retaining ring with a flared bearing surface. The presence of the retaining means may render a split socket usable; also it may assist in preventing an otherwise loose stud becoming inadvertently unscrewed.