The 4-way stretch fabric moves with you for ultimate comfort whether climbing a long transfer or racing the clock down rugged descents. The length and leg opening are designed for compatibility with knee pads, but the fit remains stylishly tailored without being excessively baggy. Since some of the best mountain biking is in the summer under the hot sun, we've added perforated ventilation for superior airflow, helping riders stay cool in even the hottest competition.