Description: Coated heavy gauge hardened steel for maximum strength and resistance to corrosion Low profile design - Suits most standard marine seats Swivels have nylon slide runners for silent, smooth 360 ° rotation Dimensions: 180mm x 180mm square - Suits standard 180mm (7") mount pattern 8mm slotted mount holes for universal fit. Specification: Material: Steel Color: Black Size: Approx. 180x180mm/7.09x7.09inch Package Includes: 1 piece Chair Swivel Plate Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement