Single Thread U-Nuts are used where a full bearing surface on the lower leg is desired. During assembly, these high-performance U-shaped nuts are placed over the edge of a stamped panel, or through a pre-stamped slot. They are then simply pushed until the rear of the fastener locates against the plastic or metal panel edge or snaps into the clearance hole. U-Nuts are self-retained in screw-receiving position to provide simple, rapid attachment of mating panels. They cannot turn as the screw is driven.