Monarch Marine Black Flat Piling Cap - 7.5in. Black caps are made from heavy UV-resistant low density polyethylene with a very long life. The actual life of piling caps is not guaranteed. Specifications for Monarch Marine Black Flat Piling Cap: Manufacturer: Monarch Marine Color: Black Package Contents: Monarch Marine Black Flat Piling Cap Monarch Marine BFPC-7.5: Black Flat Piling Cap - 7.5in