1. Dive/pre-dive lever for adjusting breathing effort with the Venturi Effect.2. OWS System: front shield and button in soft polyurethane to optimize the action as well as the passage of water, reducing breathing effort, and thanks to the synergy between the front and side openings, it avoids the chance of free-flows in head-on currents.3. The special geometry of the exhaust tee prevents water from seeping into the second stage even when in powerful side currents, and also directs expelled bubbles to the sides of face, eliminating annoying obstructions in your field of view.4. Hose retainer features a carefully researched length and diameter to avoid any pinch points. Optimized curvature, ergonomic for users.5. First stage made using mechanical processes. All ports, both HP and LP, are arranged radially. Simple piston. 1 HP port. 4 LP ports.2