Skirt made of soft silicone Valveless breathing system One direction airflow Snorkel top with dry system preventing water entry Adjustable elastic strap Duke Dive Mask is a full-face mask (FFM), and it is designed to give the user the opportunity to breathe easily. Duke mask implemented a new system of breathing with a lateral tube position that doesn’t require the need for forced breath to travel a longer distance and open more than one valve. The reason why Cressi has chosen to position the tube laterally is that it is the shortest route possible for airflow with minimal effort. And this is currently under patent. The left-side tube is divided into two before entering the two separate chambers. One is connected to the breathing chamber and the other is connected to the vision chamber. A minimal build-up of residual CO2. The extraction chamber has an enlarged volume in order to allow for optimal CO2 extraction. The airflow system in Duke produces far less co2 build-up than a safety gas mask. Cressi tested it in the laboratory of Milan polytechnic’s engineering department where the results were beyond their expectations. An excellent Anti-fogging effect. The second independent tube is connected to the vision chamber and extracts moisture and warm air that builds up in this chamber, completely separate from the breathing chamber. Duke has a deflector, which is also under patent, which maximizes the extraction of warm air produced by the face when the mask is worn, and it is designed to work like a chimney effect forcing air circulation away from the lens. These advantages are enhanced by the fact that neither the breathing chamber nor the tube has any valves to impede the user’s breath. But Duke has large outlet valves at its base, to drain the mask quickly and easily if it fills up with water. Additionally, one large outlet valve below the mouth has nothing to do with the breathing system.