Very durable cast iron cylinder with oval exhaust port and 6 transfer ports. Very good performance right through to the upper rev range makes this a top choice all-rounder for those who are looking for a powerful and reliable cylinder. The supplied ASSO piston has a chromed piston ring and a cast piston ring. The chrome ring should always be used in the top ring groove. The trophy is supplied with a high squish band. New version comes with a cylinder head! Be aware that some shops are still selling the older, cheaper version without the head!