This 4 inches screw-in deck plate is made of anti-aging, anti- and UV-resistant plastic with finish.Deck Plate is leak-proof. SCREW-IN style has a single-, non-jamming (no -threading). Separate cover plate and chassis for easy installation. Screws not included.Use silicone sealant on the hull or deck surface when installing the deck plate. Round Inspection Deck Plate HatchMaterial: plasticColor: WhiteFinish: Inside Diameter: 4 InchesSeparate cover plate and chassis, very easy to installPackage Contents:1 x boat hatch coverOnly the above package content, other are not included.Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.