This is a swim cap from petit main. There are creases on the brim. It should be fine to use. How about it for sun protection? This is a simple and easy-to-use swim cap with a single-color design. The front has a brim, and the back has a sunshade cloth to effectively cut off UV rays. The generous gathering creates a frill with a strong presence. The fabric stretches well, providing an excellent fit. Size) Head circumference x Height x Brim x Sunshade length S) 42 x 4.5 x 9 x 11 Season: Summer Color: Yellow Pattern/Design: Solid Rash guard