PES fabric is an acrylic-coated 100% woven polyester (600 denier) utilizing a proprietary process to coat both the top and bottom, thus allowing the fabric to be completely reversible. It is characterized by excellent strength, durability, tear and abrasion resistance, dimensional stability, UV and mildew resistance. This fabric was originally developed to cover military vehicles in the desert, so you can be sure it will protect your porch. We describe it as super attractive, yet very durable! Did we mention is also doesn’t fray?