Stellex Pontoon Boat Cover Blue Medium. With tough Stellex™ fabric designed for durability and weather protection, this is a great all-season cover that fits most popular pontoon boats. Rope attaches to rugged non-scratch D-rings so there are no grommets to pull out or scratch. The adjustable transom flap and elastic cord sewn into the bottom hem provide a tight, custom fit. This cover is resistant to milder and UV damage.