4 oz., 100% polyester. Three-button placket with flat knit collar. Double-needle top-stitch on bottom hem and side vents. Inside neck is clean finished with self fabric neck tape. Performance fabric provides greater comfort during strenuous activity and intense play. It is proven to absorb, wick and evaporate more moisture than cotton. It is quick drying and breathable. Anti-microbial treatment prevents odors from perspiration. UPF 50.