PACK HELIX DIN + OCTO

The Aqua Lung Helix Pack pairs the Helix regulator with the matching Helix Octopus, which is the cheapest way into an Aqua Lung set where the alternate is built to the same standard as the primary. Both stages of the Helix are balanced, so breathing effort stays level as the cylinder empties.

The first stage is a balanced diaphragm design supplied with a DIN 300 bar connection, weighing 475 g. Its ports sit in a T layout, two high-pressure in 7/16 inch UNF and four medium-pressure in 3/8 inch UNF, which routes the primary, the octopus, an inflator hose and a gauge without crossing hoses. Work of breathing on the primary is 0.85 j/L and on the octopus 1.25 j/L. An in-line Venturi knob adjusts the primary and can be turned wearing thick gloves. The octopus runs on a high-visibility yellow hose.

The result is a first set of regulators that a diver keeps rather than replaces, because the parts are serviceable and the breathing performance is not entry level.

Supplied as a first stage, primary second stage and octopus. A pressure gauge or transmitter is sold separately, as is the DIN to yoke adaptor. The regulator is compatible with nitrox up to 40 percent oxygen from new, and the Helix Pro pack is the version to choose for water cold enough to need an Auto Closure Device.