Used Mercury Mercruiser General Motors GM flywheel 366861N . Approximately 12 7/8″ in diameter, 153 teeth. The ring gear and teeth are excellent and there is only cosmetic corrosion to the flywheel. Skippers Marine specializes in new old stock, recycled and those hard to find marine parts and accessories. Please check out my other Ebay store items. Don’t see what you are looking for? Feel free to send an email request. 6-0256