95% UV Blockage Blocks 95% of harmful UV, significantly reduce the temperature and UV sunlight in shaded area during summer time, ideal for patio, swimming pool, balcony, carport etc. Breathable fabric allows water and air to go through freely, no pooling water in rainy days, resistant to both UV and water, no maintenance needed. Permeable Fabric Material Material is made of virgin (non-recycled) high density polyethylene, fabric has been treated with UV stabilized compound, preventing shade sails from dried out, tearing and fading, significantly extend the lifespan, also let the air and water to go through to prevent pooling water and catch less wind. Rust Free D- Ring D rings are attached to each corner for easy installation, made of 314 rust free stainless steel, bigger and stronger than competitor's, corners are constructed with extra amount of stitched seams to maximize the strength of D rings. Curved Edges Edges are made slightly curved based on precisely calculated radian, helps shade sail to stay tight and neat after installation, prevent shade sail from sagging in the middle for best appearance and performance. How to Measure Shade sail's measurement should be taken from corner to corner. Approximate how much area you want to shade. Locate 4 mounting points, they can be roof, trees, poles, wall, etc. Take measurement of the 3 mounting points, leave 0.5 ft to 1 ft space for the hardware kits between the shade sail and the mounting points. Install the hardware kits on 3 mounting points. How to Install If the space between shade sail and hardware kit is more than 1 ft, use cable wires as extension, to connect the shade sail to the hardware kits. Install the shade sail, connect the D-ring to the hardware kits or cable wires. Adjust the turnbuckles to create tension.