Polyform Elite boat fender covers are as tough as the fenders they protect. Polyform uses a premium grade yarn that is resistant to sunlight, UV breakdown and abrasion. They are woven by a special knitting machine that produces a seamless tube (so you don't have to worry about seams splitting) and allows for a heavier yarn content. The result is a fender cover that is built to last for many years and not just a season.