John Edwards from Coverworks uses I exclusively use the best material he can find, 'Exterior Marine/Awning grade Sunbrella', color fast, breathable, resistant to sun, mold, mildew, atmospheric chemicals, salt, rain, freezing, etc. and comes from the manufacturer with a 10 year warranty (excluding my labor). The best warranty in the industry. Sunbrella is the same material you see used in the marinas the most for boat/sail covers.
Seams are double sewn waterproof style, seam edges turned under and sewn "French style". Heavy 18oz. 'Shelter-Rite' nylon reinforced vinyl (truck tarp) is sewn inside around the table top section (6" wide band) and inside the very top to protect from rubbing against edges of table and top of hat (damper. There's a matching sunbrella handle sewn flat into the top; comes in handy for handling the covers during install/removal and can also be used to hang the cover while not in use. Tabs with grommets are sewn inside along the bottom edge for additional restraint.Click Here if you want to contact John at Coverworks for a quote. You'll need pictures and measurements from every angle.