Pearl iZUMi Women's Woolie Seamless Arm Warmer The Woolie Seamless Knit Arm Warmer offers the comfort and warmth of wool with the moisture management of high-tech polypropylene Wool and Polypropylene yarns offer warmth and superior moisture transfer Tunneled elasticized construction for an optimal fit Easy on and off versatility Highly packable Sizes: SL Content: 38% Nylon/ 32% Wool/ 26% Olefin/ 4% Elastic