Reliable Marine Battery Connections Made SimpleThe T-H Marine Marine Battery Terminal Kit is designed to convert an automotive style post to a marine wing nut style battery connection. Built from durable corrosion-resistant materials this kit is made for harsh marine environments and fits most standard marine batteries. It provides secure dependable connections to help keep your boat&';s electrical system running smoothly. Color-coded marine terminal kit Designed for 12V marine systems Converts automotive post to marine wing nut style Negative post size is 5/16 inch Positive post size is 3/8 inch