Upgrade your stationary boat chair to a swivel-style seat with this Wise Boat Seat Swivel mount. It features an interior ball bearing that allows for an effortless and smooth motion and has a zero-degree tilt. This black boat seat base is constructed from steel and has a durable powder-coated finish for weather resistance.Specifications and Features: 6" boat seat swivel base Black powder-coated steel Designed to fit BIA standard 5-1/4" pattern, 4 hole seats Nylon bearing boat seat swivel