We use 9.25 oz. of 100% Dolan® solution dyed acrylic fiber. Solution dying is a unique process in which the pigment or dye is added, along with UV stabilizers, while the fiber is still in viscous form. This locks the color in so that it cannot be faded by the sun or even bleached out with chlorine bleach! Additionally, the UV stabilizers keep the sun from “dry rotting” the fabric to the point where it loses strength and can literally “turn to dust.” Solution-dyed acrylic is a natural at resisting stains, but we also add stain release finishes to make our fabrics even more stain-resistant. Acrylic will not support the growth of mildew, which is why we guarantee our canopies for 6 YEARS!