A shirt that''s easy-wearing and hard-working. This button-down is made of 100% recycled fabric that wicks moisture and provides UPF 40 sun protection. It dries fast and stays airy thanks to built-in vents. A summer-loving shirt features some of Columbia''s best sun protection with UPF 40 to block UVA and UVB rays. Moisture wicking fabric includes antimicrobial treatment and mesh lined venting to keep you feeling fresh all day. This Columbia button-up shirt comes in many sizes and colors. Available in extended sizing. Regular Fit. To ensure the size you choose is right, utilize our sizing chart and the following measurement instructions: For the chest, measure at the fullest part of the chest, under the armpits and over the shoulder blades, keeping the tape measure firm and level.