This quality of UV rays UV protection and compact, flat umbrella offers the highest UV protection and quality of any UV protection umbrella on the market. With a 55 + UPF (Ultra Protection Factor) Rating, this umbrella blocks 99% of harmful UV rays The sun (a, b, c). This sun umbrella is made from a specially treated Solarteck fabric which thanks to the high quality of the UV rays while youre up to 15 degrees cooler in sunlight. The patented vented mesh system, lets the wind between the upper and lower canopies to keep you cooler while providing optimum ventilation and stability and works great in the rain.