Custom bumpers come in all shapes and sizes. To begin, you should have a rough idea for a design. Some of the most common are sheet metal bumpers which tend to be heavier but are very durable and can complement the front end of some vehicle better than the tube bumper style. The alternative style, as mentioned, is tube-style front bumpers, these consist primarily of welded steel round tubes which create an incredibly strong structure and are also complimented with an aluminum skid plate (for front bumpers).