These webbing sails do not require cabling for stability. The rigid edge and clean corners allow the sail to be pulled tight in order to avoid wrinkling and sagging. Commercial 95 shade/mesh fabric offers the ultimate combination of maximum sun protection, strength and durability to ensure maintenance-free, long-life performance. D-Rings are included with the sail. The hardware to attach to posts is sold separately. Shade products are non-refundable. Prior to installation, research any relevant building regulations which may exist, and check with the local utility companies for any underground services prior to digging holes for the support posts. Do not have fire or an open flame close to the fabric. Do not use your barbecue under the shade structure. The provided fabric will measure 18x20 feet.