GC2B/30 - 30" Hose with Male Gas Connector to standard (9/16" UNF female) 2nd stage end – Series B - March 2024 on

The GC2B/30 is one of the hoses in the new High-Flow, Dry-Connect-Underwater, Gas Connector System.

Launched in March 2024 the AP Gas Connector System (Series B) is a new and improved system that replaces the previous GCS (Series A).

PLEASE NOTE: The B Series connectors are NOT compatible with Series A connectors (including the Auto Air connector).

The GC2B/30 is a 30" hose - the male half of the GCS - with a Male GCS connector (to connect to the female hose GC1B/30) on one end and a standard (9/16" UNF female) 2nd stage connector on the other.

The GC2B/30 gas connector hose allows you to feed gas to either the OCB (BOV) mouthpiece, the ADV (Diluent Add) or a second stage when used together with a GC1B/30 female hose which is, in turn, connected to a first stage (of an on-board or off-board cylinder).

NOTE: All hoses can be shortened by unscrewing one of the reusable end fittings and cutting the hose to the required length.
The end can then be re-fitted.  Hose Shortening Instruction Video

Longer hoses are available on request.*

*IMPORTANT NOTE: The EN250 standard performance is achieved with the  30” (76cm)  AP regulator hose. If longer hoses or other manufacturer’s hoses are used with the AP connections, the breathing performance will be different and may fall outside EN250.

Introducing the new high performance AP Gas Connection System:

High-Flow, Dry-Connect-Underwater, Gas Connector System

• The new High-Flow system is rated to EN250 breathing performance down to 50m.

Higher flow is achieved by the mechanical opening of internal valves in both the male & female connectors.

• The new GCS is an Dry-Connect-Underwater system.

• The GCS can be connected underwater with or without pressure in the line.

Both male and female connections feature an automatic closure so that water cannot enter when disconnected and you do not push a slug of water into the hose on connection.

The dry system significantly reduces the probability of a free flow caused by water travelling to the second stage as a mist and then freezing the internals in cold water conditions. A dry environment also reduces internal corrosion increasing the longevity of the products.

• Versatile Quick-Connect System

• Ergonomic design with easy-grip large collar and knurled rings on the female connector offers a simple push together/pull apart quick connect and disconnect.

• The GCS male & female connectors are attached to the hose via a standard (9/16" UNF) 2nd stage thread connection and can therefore be fitted to other make hoses with 9/16” regulator fittings.

• Also available: a GCS Male Connector with a 3/8” UNF Female (GC2B/F) to allow connection to the 3/8”UNF end of other make hoses.

The GCS is a versatile system that can be used in multiple different configurations according to preference and the requirements of the dive, including the ability to plug in a multitude of off-board gas supplies to either the OCB, the ADV or to the rebreather manifold.

IMPORTANT NOTE: The GC3 FLOWSTOP MUST NOT be used in-line with the GCS system for open circuit use as the GC3 will significantly decrease breathing performance.