This Garelick Locking Stainless Steel Seat Swivel is a heavy duty swivel that offers 360-degree rotation and is a sturdy mount for a seat (sold separately). It locks in 12 positions at 30-degree increments for the most stable seating. It features heavy duty stainless steel construction that is suitable for use in offshore conditions. It fits most standard seat hole patterns, and features a self-lubricating, non-corrosive poly swivel bearing. This swivel measures 7-In. x 7-In. (18cm x 18cm). Garelick's advanced design and engineering capabilities allow us to produce a wide variety of stable and safe seat and table pedestals, swim ladders, and marine hardware products for any boat configuration.