The United States Postal Service operates the Civic Center Van Nuys Post Office at 6200 Van Nuys Boulevard in Van Nuys and the Van Nuys Post Office at 15701 Sherman Way in the Lake Balboa neighborhood in Los Angeles, west of Van Nuys.
One of my favorite Split Bumper Camaro street race cars on the planet. Owned by Monza from the TV show Street Outlaws. This car ROCKS! One of my favorite Split Bumper Camaro street race cars on the planet.
The bumpers have a design and a crash function. That is why they are made of plastics or composite materials or fibers. By the way your question is phrased, you are looking for suitable materials to build a bumper, not a dissertation on how modern bumpers are made.