William McComas Byron Jr. is an American professional stock car racing driver. He competes full-time in the NASCAR Cup Series, driving the No. 24 Chevrolet ZL1 for Hendrick Motorsports, part-time in the NASCAR Xfinity Series, driving the No. 17 Chevrolet SS for HMS, and part-time in the NASCAR Craftsman Truck Series, driving the No. 07 Chevrolet Silverado RST for Spire Motorsports. From Wikipedia
