The ACBP is the best brass binding post made. Machined from a solid billet of Copper rich brass, then finished with Rhodium over Silver. The binding, and mounting nuts are finished in Gold. The "S" denotes "short". The "EU" denotes that this assembly started its life as a fully covered unit. This assembly "WILL NOT" come with a cover, meet EU criteria, or accept banana connectors. The ACBP S EU only accepts spades. One assembly comes with one glass filled nylon mounting block, two posts, two mounting nuts, two Teflon washers, and two binding nuts as pictured. These posts will not accept banana connectors. Priced and sold per assembly.