Used Mercury Mercruiser Thunderbolt IV module V/8-22, 8C31A. Removed from a running motor due to a repower and has been in storage. No further testing has been done. 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. 4-9835