Abstract: A fastener for retaining two adjacent edges of a pair of panels against the surface of a structure includes a head with an eccentrically disposed stem extending therefrom. A flange section around the stem is spaced from the head. Projecting sections extend from the stem below the flange. The projecting sections extend through an opening in the surface of the structure and retains the fastener therein.

Abstract: A guard beam is disposed below the bottom of the rear end of a trailer or truck. Energy absorbing members are connected between the trailer and the guard beam. When impact forces applied to the guard beam exceed predetermined minimum levels, the guard beam collapses and energy is absorbed in the absorbing members during the collapse of the beam.

Abstract: Vehicle bumper having high yield strength and extensive movement under impact loads with full shape restoration, comprising a thin transversely curved high strength resilient front plate, a high strength resilient rear backing plate located at a distance behind the front plate and anchored to the vehicle, and an intermediate body of an elastomeric material between the front plate and the rear plate to absorb impacts, increase the yield distance and to assist in restoring the front plate to original shape, together with a soft yieldable front jacket with a scuff-resistant outer surface which covers the bumper and, if desired, adjacent parts of the front of the vehicle.