The Railblaza SidePort Mount is a versatile, multi-functional vertical mount. This mount is best suited for gun whales of smaller aluminum boats, vertical cockpit wells on kayaks and applications that have a vertical surface, but require a horizontal StarPort. Designed to be mounted on a vertical surface and provide a horizontal socket, Allows users to fit and swap out the full range of Railblaza accessories, Made from high grade engineering plastics, Diameter: 2.4 in., Bolting Dimensions: 1.9 in o.c., Model Year: 2019, Product ID: 430486, Model Number: RBSIDE, GTIN: 0856154004186