The Mares Ultra Adjustable Octopus Regulator is designed for use with the Mares Ultra Regulator Series (see SKU’s: MRSUA82X, MRSUA82XD, MRSU72X). Vortex Assist Design (V.A.D.) system: all Mares second stages offer the unique patented VAD system. The air bypass tube conveys air to the mouthpiece creating a swirling vortex with a low-pressure area in the center this keeps the diaphragm down during inhalation, giving very sensitive and easy breathing at all depths. The bypass has undergone a true transformation: 77% increase in flow cross section and double curvature to provide a smoother flow while optimizing performance. For the first time a Mares second stage regulator is equipped with a flow control (Twin Power), managing the delivery rate of gas from natural breathing to power breathing. By rotating the adjustment sleeve on the hose inlet, you can achieve VAD+ performance. Octopus is made of ultralight techno-polymer with a wide pivoting purge button. This pneumatically assisted designed (P.A.D.) safe second is equipped with an adjustable breathing knob for the ultimate in breathing comfort. Ultra Adj features a breathing resistance control knob on the left side of the regulator. Optimum performance is delivered when the knob is turned all the way out (counterclockwise when looking at the knob). For specific situations in which you require a higher breathing resistance, turn the knob clockwise to add compression to the spring acting on the demand valve. Furthermore, the compact and ergonomic exhaust tee ensures superior hydrodynamic performance and reduced exhalation resistance. The mouthpiece is made of soft hypoallergenic silicone: limiting jaw fatigue and offering a secure fit even after very long dives. Mares developed the Superflex hose after many years of testing and research. The results achieved far surpassed the tests required by EN250. Hose is extremely light weight and exceptionally soft, guaranteeing the maximum freedom of movement and further reducing jaw fatigue. The regulator comes with a high visibility yellow Superflex hose that is a 3/8″ threaded high flow hose and is 39.4″ (100cm) in length. The regulators total weight is 12.2 oz. (346 g) with hose. Regulator is Nitrox ready up to 40% oxygen out of the box.