Wise 8WD013 Standard Pilot Chair & Cushions and Pre-Mounted Universal Mounting Plate with T-Nut inserts. Mounts to any 4 Bolt BIA Standard Pedestal System Thick wall rototional molded, high impact marine grade plastic external frame, includes a pre-mounted universal pedestal mounting plate with T-Nut insert Snap-on cushions with compression foam padding with mesh underlay to expel moisture; Features embossed vinyl surface detail and embroidered logo Heavy Duty Marine grade 28 oz. vinyl withstands the effects of sun, heat, rain and soiling under normal conditions SEAT DIMENSIONS - Height: 18.25" Width: 16" Depth: 19.5" Sitting Depth: 16"