Swivl-Eze Lock'N-Pin 7" x 7" Threaded Deck BaseSwivl-Eze is the #1 supplier of 3-4" pin seating hardware Here's why: The 3-4" system gives you outstanding economical performance; The design is proven by decades of experience; Posts are available as fixed, manually adjustable, or power-adjustable; Seat mounts, posts and bases available in steel, aluminum, or stainless steel; 7" x 7" Base plate, Threaded, Nylon Bushing;