The Halcyon Halo Second Stage offers steadfast reliability and impeccable performance; two methods of breathing adjustment make it the top choice for demanding divers.

The Halo provides amazingly smooth performance in all conditions providing unsurpassed performance with enhanced technology.

Breathing underwater should feel natural, and that experience is one of the things that most clearly separates Halcyon’s second stages. You will be hooked as soon as you experience the smooth, high volume of air delivered by a Halo.

Balanced, adjustable downstream valve

Balanced, downstream valve offers incredibly smooth breathing in all conditions. The design slightly offsets the force of the downstream air entering from the first stage, allowing reduced spring tension and a decreased inhalation resistance.

Halcyon’s first stages are balanced, so the Halo perfectly fits the Halcyon H-75P or Halcyon H-50D first stages.

Adjustable inhalation control

Adjustable inhalation control refines breathing effort through an easy access control knob; this allows the demanding diver to fine-tune the second stage’s air delivery.

Air Control Vane

Air Control Vane (ACV) offers a second diver adjustment for the ability to fine-tune breathing. The ACV uses vacuum-assist technology to reduce the work of breathing and increase diver comfort.

This level of refinement is available on all Halcyon second stages. ACV in the “dive” position gives powerful breathing support, while ACV in the “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.

Comfortable mouthpiece

Comfort mouthpiece is standard in every second stage to reduce jaw fatigue and mouth irritation. This long-lasting mouthpiece requires only a minimum effort to hold comfortably in place.

Combined 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.

Halcyon Halo Second Stage features

Compatible with 40% Nitrox (outside the EU)
40” (100cm) rubber regulator hose included
Adjustable downstream valve
Air Control Vane

⏎ Download the Halcyon Regulators Manual

1st Stages | 2nd Stages

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