Docking can be treacherous - it's a minefield of corners and edges that can cause damage. Protect your dock and boat with dock bumpers. These bumpers are constructed from a closed cell foam padding that won't deflate or collapse and are designed with four grommets for secure mounting. Impervious to sunlight and tearing. Constructed with a marine-grade tri-laminate cover, double thermal-bonded seams, and polycarbonate grommets. Dimensions: 12" long (each side) x 6" tall x 4" thick.