Thick blackpowder coated aluminum marine dock pile caps with waterproof lid for piers, docks and other water post applications. Used to prevent water damage, sun damage and general wear and tear from the elements which will preserve the top surface of dock pilings and deter rot and deterioration and costly repairs. Heavy duty 26 gauge blackpowder coated aluminum lids will add nice looking accents to your piling posts. Available in 1 inch size increments online, up to 16" diameter and please contact us for optional 1/2 inch increments.