Tension is evenly distributed so the fabric remains flat and does not sag.
PRODUCT FEATURES:UV Blocking92% Shade RatingStainless Steel D-RingsIncludes 5' PE Ropes for Installation 1 per sideAVAILABLE SAIL STYLES:TriangleRectangleSquareSEASONAL SHADE and SHELTERPerfect for adding shade and ambiance to a backyard, patio, deck, porch, balcony, pool, driveway, pergola, or garden.HIGH TENSION and STABILITY WILL NOT SAGConcave sides offer maximum stability.