SAS Cool Step Footbed uses an anti-bacterial foam material that aids in wicking moisture from the foot's surface. Cool Step O2 foam is engineered to be firmer and more supportive under the heel for stability and softer under the forepart of your foot for cushioning. The O2 Airflow cover on this helps in reducing the friction that can cause heat buildup underfoot. The heel is cupped for a cradle-fit. The SAS Cool Step Footbed gives the wearer a much 'cooler', more stable, comfortable walking experience.