Dock Bumper Fender Slide-Over Post, Dock Guards Vertical Protection for Boat, Dock Leg Pipes Pole and Mounting Brackets The dock bumpers for poles built in a molded-in air valve for easy inflation and deflation Ribbed construction and rugged cushion provide maximum protection for dock leg pipes and mounting hardware of docking system as well as your boat Crafted from marine grade soft vinyl which resistant to UV, fading, tearing, chalking, splitting or crushing as well as the harsh marine elements; Heavy-duty roto-molded for long lifespan and durability Vinyl post bumper slides over dock leg pipes and mounting brackets to prevent damage to your craft from protruding bolts and protect boat from hitting the dock brackets hardware and damaging the dock pole Just slide over the dock posts, the dock fender bumper will provide protection to your boat and dock leg pipe with simple and easy installation