Common to all carders is card clothing. Card clothing is made from a sturdy flexible backing in which closely spaced wire pins are embedded. The shape, length, diameter, and spacing of these wire pins are dictated by the card designer and the particular requirements of the application where the card cloth will be used. A later version of the card clothing product developed during the latter half of the 19th century and was found only on commercial carding machines, whereby a single piece of serrated wire was wrapped around a roller, became known as metallic card clothing.