Nylon and fiberglass: for when you want a lightweight, technical solution with calibrated stiffness that matches your need for comfort. Its the Northwave ventilation system with large vents that lets your feet breathe: the lower vent channels air inside the sole, while the side vents guarantee a supply of fresh air. Heel Stabilizer. It offers enhanced heel stability, reducing the weight of the material needed for injection to a minimum. Countless ventilation holes keep your feet fresh while a thinner design ensures you get the sensitivity and grip you need when out on your rides.