Wise 2 7/8'' Adj. 12-18'' Pedestal w/ Seat Mount Metal Small. 2 7/8'' Diameter Thick Wall Post with 9'' Diameter Base Plate with Recessed Mounting Holes. Constructed of Extruded and Cast Polished Aluminum. Cast Aluminum Seat Mount Locks and Swivels 360 Degrees with Adjustment Knob. Simply Pull and Turn the Height Adjustment Knob to Raise or Lower your Seat. BIA Standard 4 Bolt Hole Pattern fits Virtually all Seat Brands. Specifications for Wise Pedestal w/ Seat Mount: Manufacturer: Wise Seat Type: Seat Hardware Fabric/Material: Aluminum Color: Metal Width: 7 in Height: 12 - 18 in Length: 12 - 18 in Condition: New Depth/Thickness: 2.8 in Features of Wise Pedestal w/ Seat Mount Extruded and Cast Aluminum Construction 2 7/8'' Diameter Thick Wall Post. Swivel 360 Degrees Fits Virtually All Seat Brands Package Contents: Wise Pedestal w/ Seat Mount Wise 8WP21-18S: 2 7/8'' Adj. 12-18'' Pedestal w/ Seat Mount Metal Small