Bringing the Cool Comfort of Airflex Technology to Breast Collars. Patented, state-of-the-art AirFlex technology offers comfort paired with easy care thats sure to become a favorite of your trail riding customers. Breast pieces are constructed from 2" wide black nylon webbing lined in 3" wide Airflexmaterial for breathable comfort. Unique white cool flex foam doesnt absorb heat like traditional neoprene. Distinctive molded airflow channels maximize air circulation and provide ideal flexibility..