The Dorsal SS button down shirt comes features a 100% polyester base with AFBLOCK UPF 50 sun protection, AFGUARD stain resistance, and AFLITE ultralight fabric. These shirts come with many extras including vertical vents on the "dorsal" side, as well as a integrated lens cleaner for your sunglasses and eyeglasses. Features 100% Polyester Mechanical weft stretch heathered 95 gsm Integrated lens cleaner UPF 50 sun protection Stain resistance Ultralight fabric DWR stain resistance Size & Fit Regular fit