Its motorsport design and outstanding quality synonymous with CH Challenge rims form the hallmarks of this wheel. The result: the latest development from the world of motorsport is now exclusively available in 20". Technology Low pressure casting for long-lasting performance. Weight optimised by FEM analysis, manufactured in a flow-forming process specially developed for Formula One. Surface Finish: matt black or brilliant silver. Rim protector: polished stainless steel. Specials Innovative laser inscription. Weight optimisation thanks to milled spokes.