A maximum value option for entry-level UV protection. Short or long sleeve Basics U. P. F. 30+ Sun Shirts are designed to keep you covered in the sun and surf and built to last in chlorinated pools. 30+ U. P. F. Maximum Protection Strategic Seam Placement 2-way stretch Rash Protection Chlorine resistant Slim Fit Polyester Overlock Stitched: Super-Strong Seam.