These Screw-Out Deck Plates are molded to the highest standards. Keep threads clean with hot soapy water. Lubricate with Vaseline or Teflon grease. Avoid contact with acetone or strong solvents. Constructed of UV resistant and antioxidant injection molded ABS. Installs with six #8 FH fasteners (not included). When installing, use silicone sealant on hull or deck surface.