These wheels were made for a solar-powered car which competed in the World Solar Challenge. This is a race held every two years from Darwin, Australia to Adelaide, crossing the continent north-south, a distance of 1,878 miles. The wheels are 17″ (432 mm) in diameter weigh 4.8 lb (2.2 kg) each. They are machined from solid 6061-T6 aluminum plate. All machining is done on the CNC mill, with a cycle time of 16 hours per wheel.