Castelli Nanoflex Arm Warmer

Engineered by Castelli, Nanoflex and Thermoflex fabrics have been combined in the NanoFlex Arm Warmer to combat two dreaded winter elements: cold and wet. NanoFlex is a water-repellent material that prevents water droplets from seeping into the arm warmer, instead they bounce off without a trace. The fleecy Thermoflex fabric traps a layer of warm air next to your skin, and its high stretchability gives you an aerodynamic fit.