All RCD degree rings are machined from billet aluminum stock or forgings and anodized black with degree marks laser etched around the outside diameter. These degree rings have a six lug pattern machined in the center and are made to press on to all RCD crank hubs. Degree rings are available with timing marks for alcohol or nitromethane burning engines. For applications using crank trigger pickups RCD offers degree rings with rare earth magnets epoxied into machined pockets. NOTE: excessive heating of degree rings with magnets can result in de-magnetization.