As to quality Single Eye Fenders are fully up to the standards of the Heavy-Duty series. The only difference is the fact that one eye has been removed, as some sailors think that it is not necessary to have eyes at both ends which also makes the fenders a bit longer. Single Eye Fenders are less expensive, as the fenders only have one of the specially produced eyes. Available in sizes for boats from about 17 feet up to about 30 feet.