Abstract: A one-piece fastening mechanism for attaching a first member such as a molding or trim piece to a second member such as the side panel of a motor vehicle, the fastening mechanism being preferably integrally formed with the molding or trim piece and including a body portion having a first opening extending longitudinally along substantially the full length thereof and a second opening extending transversely through the body portion. The body portion and the transverse opening define a plurality of resiliently flexible barbs or detents, the fastening member being sufficiently flexible so as to be compressed during insertion into an aperture associated with the second member whereby the plurality of detents are moved into engagement with the peripheral edge portions of the aperture.