This high quality second stage regulator provides diver adjustable controls for the ultimate in breathing performance.  Halcyon’s Halo second stage offers steadfast reliability, and impeccable performance. Two methods of breathing adjustment make it the top choice for demanding divers. Halcyon first stages are balanced, so the Halo is a perfect fit with either the Halcyon H-75P or Halcyon H-50D first stage. Adjustable inhalation control refines breathing effort by way of an easy access control knob; this allows the demanding diver an opportunity to fine-tune the air delivery of the second stage.Air Control Vane (ACV) offers a second diver adjustment, for the ability to fine-tune breathing. The ACV uses vacuum-assist technology to reduce work of breathing and increase diver comfort. This level of refinement is available on all Halcyon second stages. ACV in “dive” position gives powerful breathing support, while ACV in “Halcyon” position helps prevent free flows. This can be helpful on the surface, when diving in currents, while scootering, or when the Aura is used as a backup regulator. Comfort mouthpiece is standard on every second stage, to reduce jaw fatigue and mouth irritation. This long lasting mouthpiece requires only a minimum effort to hold comfortably in place. In combination with the freedom of head movement, provided by Halcyon’s primary long hose, you will enjoy dives free from the jaw fatigue common with certain mouthpieces and/or poorly balanced hose routing. Comes standard with 100cm/ 40" hose.

High quality rubber hose - this length is best suited to decompression and stage regulators. Also is a standard octopus length.