A vacuum-formed clear plastic body offers several advantages over the stock injection-molded hard-plastic item. First, they are substantially lighter than a standard body, and usually this weight-savings translates into quicker lap times. Second, they are very inexpensive. And third, often it's the only way to get a body shell of a current racing car. BSRT, Scale Auto, Rothwell, Thunderbolt, Parma, and MaDD all make fine bodies that cover just about the entire spectrum of racing. All the clear bodies listed can be painted and decals applied to replicate existing race cars from any era.