The Buick Rainer rear bumper is nothing but a plastic piece that is bolted onto the rear or lower rear portion of the vehicle. This Buick Rainer bumper cover like the front bumper cover helps in absorbing the impact of crashes. The Buick Rainer custom rear bumper is made of carbon fiber, fiberglass or ABS plastic. The rear bumper usually is built in with a cut out, allowing space for the exhaust tip. The Buick Rainer rear bumpers are used more for styling with the several aftermarket bumpers available. The Buick Rainer also has a lot of aftermarket bumpers to choose from helping you own a car of your liked appearance.