GTPhreak is right. The new kits are urethane. I've got an original fiberglass kit, but it's still dynamite looking. Being fiberglass it did add weight to the car. My body guy said that it was the best fitting kit he had ever done. He did have reservations with the front being hung by two tabs and some screws so he custom fabbed some bracing and that turned out good so I had him brace the back and sides also. I wasn't to thrilled that the sides just "taped" on, so we fiberglassed a stud to the front and rear, drilled corresponding holes and now they are taped and bolted on. My car is a daily driver and has been in 5 different accidents (I swear I wasn't speeding) and the kit has only chipped or broken a tab, never broke in pieces or shattered. The kit is like armour, really good looking armour, that I still get complemts on everyday I drive it. Oh yeah, be prepared for everyone to race you..........