Adjustable head bracket makes for quick strap adjustments and a universal fit. V02 max – Increases aerobic capacity and builds lung endurance. Hydrodynamic tube curves around the head to reduce drag and promote proper body position. The center-mount design accommodates a full range of motion for butterfly, breaststroke and freestyle. Allows swimmers the ability to focus on stroke technique without the interruption of turning the head to breathe. The FINIS GLIDE snorkel is an introductory center-mount technique and training snorkel ideal for fitness and team training. The center-mount design allows you to be comfortable in the water, breathe easily and swim with perfect balance. A hydrodynamic tube curves around head to reduce drag and promote proper body position.