HEAVY DUTY TARP: Our four-season premium quality canvas tarp are sturdily designed and constructed to perform in all weather conditions. TIGHT WOVEN FABRIC: Our canvas pergola cover is made from loomstate heavy duty 18 oz/ 37 Mil/ 610 gsm numbered duck fabric which is Grade "A" Premium Double Filled or "Plied Yarn" of industrial-grade which creates a tighter weave construction and smoother texture than single fill cotton ducks.
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