I have the wings west avenger kit on my car, it is made out of urethane. My bumpers are real heavy, but i know they can with stand alot. I hit a dog or some kind of small animal at about 65, the only damage i had was it went threw my front grille. It actually tore the heavy stainless mesh, but it did not rip the screws out, also chipped some paint off. If i would of had a fiberglass front end, it would of been in pieces.