Hard skin mooring buoys have a seamless and tough, one-piece polyethylene shell. Hard skin shells feature ultraviolet light absorbers for long-term life under the sun. Filled with EPS foam to positively displace water. Tube-through-the-center design. Three-Year Flotation warranty. Textured finish to enhance paint adhesion. Hardware not included. Mooring chain should be 1/2" smaller in width than the tube I.D.Chain length is normally 1.5 x water depthThe chain weight should not be greater than 1/2 the buoyancy rating of the buoy