RoS stands for rain or shine, and that's exactly what the RoS Shoe Cover is made for--providing warmth while cycling in any conditions. The main fabric is windproof and water-resistant with a fleece lining, keeping your feet warm and dry when dark clouds bring moisture and the roads are wet. That being said, the material remains breathable and stretchy to keep your feet comfortable when it's dry, making these shoe covers suitable for any cold weather and not just the wet. Castelli uses contoured seams for optimal fit around the ankle, with a tall cuff that features an internal gripper to seal out water. The full-length zipper allows easy on and off, aided by a pull tab on the heel. To address road spray, critical seams were moved to the outside of the foot where they're less exposed, with the inside receiving a highly water-resistant splash guard to deal with the water spattered up from your tires.