Because a 21-foot surf ski deserved a better cover.
Jeremy created the Ultimate Cover because he was tired of fighting a stretch-fit sock onto his surf ski after every training paddle. The longer the boat, the worse the wrestling match — and at 21 feet, it was miserable.
The solution was a full-zip design in non-stretch Sunbrella Marine. Lay the cover flat alongside the boat, set the hull inside, zip the full-length YKK #10 zipper closed. One person, 60 seconds. We've since replaced every stretch-fit cover on our own kayaks, surf skis, and outrigger canoes with Ultimate Covers.
Built with the best marine-grade materials available.
Solution-dyed acrylic with a 10-year UV warranty. The marine industry standard for offshore covers.
Full-length non-marring nylon coil. Salt-rated. Dual sliders on compatible hulls.
Bow and stern tie-down points. Welded stainless steel, not sewn loops.
Three handles — bow, center, stern — for loading onto racks without removing the cover.
Every detail specified for a cover that lives outdoors on a boat that goes places.
Hull-specific patterning
Cut to your exact make, model, and version from our pattern library. Not adapted from a generic size chart.
Sunbrella Marine fabric
Water-resistant, breathable, UV-blocking, solution-dyed acrylic canvas. 10-year warranty against fading and degradation.
Full-length YKK #10 zipper
Non-marring nylon coil runs the full length of the cover. Two-way sliders on hulls without over-stern rudders.
Welded stainless D-rings
Bow and stern tie-down points welded from stainless steel — not sewn loops that can tear under highway loads.
Three reinforced handles
Bow, center, and stern webbing handles for loading onto racks or flipping a covered boat without removing the cover.
Reinforced seams
All seams reinforced at stress points. Built to hold under highway wind loads and years of outdoor exposure.
A covered hull stays new. An uncovered hull doesn't.
UV exposure is the primary threat to any boat's longevity. It fades and chalks gelcoat, yellows epoxy, degrades composite layups over time, and ages plastic hulls. A custom-fit, breathable Ultimate Cover prevents all of those things — the Sunbrella Marine canvas blocks UV and allows moisture and heat to escape.
Beyond UV, the cover keeps road grime, bug splats, tree sap, bird droppings, pollen, and airborne grit off your hull. That means your gelcoat doesn't take a constant beating from micro-abrasions and a clean hull that's ready to paddle when you are.
The difference shows up in hull condition and resale value. A well-protected composite or plastic hull retains significantly more value at trade-in than one that's been sitting uncovered. For boats that are frequently car-topped or stored outdoors, the cover pays for itself within a couple of seasons in higher resale value and hull longevity.
Works with your rudder, not around it.
Under-stern rudders pass through a 12-inch slit in the bottom of the cover. Over-stern rudders are accommodated with openings, Velcro flaps, and closures specific to your rudder system and positioning.
Rudders are not enclosed within the cover. Enclosing a rudder creates fabric that flaps against fittings and hardware at highway speed and wears through quickly. We leave the rudder exposed and build the closure around it.
Select your rudder type when ordering. If you're not sure which option applies to your boat, send us a photo and we'll sort it out.
What you should know before ordering.
Should I add padding?
Generally, no. Padding traps grit, sand, and moisture against the hull and takes longer to dry. We only have padding on one of our own Ultimate Covers — our most fragile, lightweight ICF K1 that's stored indoors at a shared facility.
If you store your boat in a club or public boathouse where others handle it, padding can buffer against the unavoidable bumps. Otherwise, the Sunbrella fabric alone provides excellent abrasion protection.
Should I add drains?
It depends on how you store and transport your boat. Sunbrella is highly water-resistant but not waterproof. In heavy rain, some water will enter the cover.
If you store or transport your boat upside down (zipper on the bottom), any water that enters exits through the zipper. This is how we recommend storing and transporting — no drains needed.
If you keep your boat right-side up outdoors where rain falls on it, add the drains. We install reinforced mesh drains in the bottom of the cover depending on boat length and rudder configuration. Residual moisture evaporates through the breathable Sunbrella.
My boat isn't listed in the pattern library.
We make all of our patterns from measurements and don't need your boat in the shop. Our kayak cover measurement guide walks you through everything we need and lets you submit your measurements online.
Covers for one-off or out-of-production boats may require a $40 patterning fee if we determine that future orders for the pattern are unlikely.
Can I get an Ultimate Cover for my open canoe?
We don't offer full-zip Ultimate Covers for open canoes — the circumference is too large for a zipper closure to work well. For canoes, the Canoe Coat provides Sunbrella Marine storage protection with quick-release buckle straps, and the Original Canoe Cover provides stretch-fit transport and storage protection.
Installation, use, and care.
Detailed instructions for installing your Ultimate Cover, using it for transport and storage, caring for the Sunbrella fabric, and getting the most out of your cover for years to come.
Your hull is covered. Now outfit the rest of your boat.
The Canoe Coat
Sunbrella Marine storage protection for canoes. Custom-fit with quick-release buckle straps. The best outdoor storage cover you can get for your canoe.
See the Canoe Coat →Outfit Your Boat
Gunwale Bags, Tether Tabs, Paddle Pockets, and more. Purpose-built accessories designed from real paddling experience.
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