Magnum 6" cuff. The Aireator is the original airflow design that changed how modern endurance socks are made. With its trademark venting mesh weave foot, durable 6" StayFast cuff, and durable heel and toe, the Aireator guarantees long-lasting performance. Made with CoolMax EcoMade , from recycled resources.Composition: 60% Nylon, 39% COOLMAX EcoMade, 1% Lycra. Sizing: Small (Women 6-8); Medium (Men 7-9 / Women 8.5-10.5); Large (Men 9.5-11.5 / Women 11-13); Extra-Large (Men 12+).