Baseball caps were originally invented as athletic equipment for baseball players to keep sunlight, rain, and perspiration out of their eyes. Since then caps of similar design and function have achieved a large popularity in other sports and the general population. There are many designs and variations to allow adjusting the size, moving the visor, decorating the front of the cap, cut-out sections for hair and airflow, insertion of spacers or bands for absorption of perspiration, imbedded lights and varying shape designs. There are also designs for creating a cap that cools a wearer involving electric fans in the bill, detachable cold packs, circulating water tubes, and more. There are no designs however, that enhance the natural cooling of air flow.