Pearl Izumi Men's Pro Sock 91% Polyester 6% Nylon 3% Spandex Made in US Spring/Summer 2013 The PRO Sock, the first sock with Minerale yarn, providing industryleading moisture transfer with compression fit bands to make the ultimate sock The perfect balance of anatomic fit, performance engineered materials and the personal interface between athlete and gear A clothing system that works to help you maintain the perfect temperature for the weather conditions and activity range day in and day out