Apeks XTX50 Sidemount Regulator Set

A proven, cold-water capable sidemount regulator package built around the Apeks DST first stage and XTX50 second stage.

The Apeks XTX50 Sidemount Regulator Set brings together one of the most established regulator combinations in technical diving in a complete package configured specifically for sidemount.

Using two Apeks DST first stages with 5th ports and two XTX50 second stages, the system provides excellent hose routing, dependable breathing performance and the flexibility needed for a clean sidemount configuration.

Whether you're moving into sidemount for the first time or upgrading an existing system, this is a regulator set designed to be dived rather than adapted to fit the job.

Why we like the XTX50 for sidemount

Sidemount places different demands on regulator configuration compared with a conventional single-cylinder setup.

Hose routing matters.

First-stage orientation matters.

The ability to configure each side of the system cleanly matters.

That's where the DST/XTX50 combination works particularly well.

The DST's rotating turret and fifth medium-pressure port give you considerably more freedom when positioning hoses around the cylinders, while the XTX50 provides a compact, adjustable and proven second stage.

The result is a clean, practical sidemount regulator configuration without unnecessary hose bends or clutter.

Key benefits

Complete twin-regulator sidemount package
Two Apeks DST first stages with 5th ports
Two Apeks XTX50 balanced second stages
Excellent hose-routing options
Rotating first-stage turrets
Environmentally sealed first stages
Designed for demanding and cold-water diving
Adjustable breathing resistance
Venturi control
Reversible XTX50 hose configuration
Long-hose configuration included
Twin compact SPGs
Suitable for recreational and technical sidemount diving

What's included?

The Apeks XTX50 Sidemount Regulator Set includes:

2 × Apeks XTX50 second stages
2 × Apeks DST first stages with 5th ports
2 × Apeks SPGs with 8" HP hoses
2 × 10" BC/inflator hoses
1 × 65 cm / 26" regulator hose
1 × 2.1 m / 7 ft long regulator hose
1 × 90° second-stage elbow
1 × 75 mm stainless-steel bolt snap
Bungee cord
Cable ties and O-rings
Apeks regulator bag

This gives you the core components required to build a streamlined left and right sidemount regulator system.

Apeks DST First Stages with 5th Port

The Apeks DST has become a particularly popular first stage for sidemount, stage and technical diving, and there is a good reason for it.

Its rotating turret allows the medium-pressure hoses to naturally follow the orientation of the cylinder rather than forcing them through tight bends.

For this sidemount configuration, the DST is fitted with the important 5th medium-pressure port at the end of the turret.

This provides additional routing options for the second stage, wing or drysuit inflation hoses and makes it much easier to achieve a tidy configuration on both sides of a sidemount system.

Over-balanced diaphragm design

The DST uses Apeks' over-balanced diaphragm design. As depth increases, the system allows intermediate pressure to increase slightly faster than ambient pressure, helping maintain breathing performance as depth and gas density increase.

Environmentally sealed

The first stage incorporates an environmental dry sealing system, keeping water away from the main spring chamber.

This helps protect the internal mechanism from:

Cold water
Ice formation
Silt
Sediment
Contamination

It's one of the reasons the DST has developed such a strong reputation amongst UK, technical and overhead-environment divers.

Apeks XTX50 Second Stages

The XTX50 is a pneumatically balanced second stage designed to provide smooth breathing across a wide range of diving conditions.

The diver has control over both breathing resistance and Venturi assistance, allowing the regulator to be adjusted to suit the dive and personal preference.

Adjustable breathing resistance

The external adjustment knob allows you to alter the inhalation effort of the second stage.

Once underwater, the regulator can be opened up for extremely comfortable breathing while still giving you the option to increase resistance where required.

Venturi control

The integrated Venturi lever provides additional control over airflow through the second stage and helps manage unwanted freeflow when the regulator isn't being breathed from.

This is particularly useful on sidemount systems where one regulator may temporarily be parked or stowed.

Reversible hose configuration

One of the XTX50's particularly useful features for sidemount is its ability to be configured for left or right-hand hose entry.

This allows the two second stages to be configured specifically around the left and right cylinders rather than forcing both regulators into the same orientation.

Conversion should be carried out by an appropriately trained Apeks service technician.

Built for UK diving

The XTX50/DST combination is particularly well suited to the type of diving we actually do in the UK.

Cold water, deeper diving and demanding conditions place very different requirements on a regulator compared with warm-water holiday diving.

The environmentally sealed DST first stages and proven XTX50 second stages make this a regulator package equally at home on a recreational sidemount dive as it is progressing into more advanced technical diving.

A regulator system you can grow with

One of the biggest advantages of choosing the XTX50/DST combination is versatility.

You're not buying regulators that only make sense for one particular configuration.

The same core regulator platform is widely used for:

Sidemount • Stage cylinders • Decompression cylinders • Twinsets • Technical diving • CCR bailout

That makes the Apeks XTX50 Sidemount Set a particularly sensible choice if your diving is likely to develop beyond your current qualification.

Need help configuring your sidemount regulators?

A good sidemount regulator system is about more than simply connecting the correct hoses.

Hose lengths, first-stage orientation, second-stage position and cylinder configuration all affect how cleanly the system dives.

If you're unsure about your configuration, speak to the ScubaDiving Gear Store TecLAB.

We can help you configure your Apeks sidemount regulator system around your equipment and the way you actually dive.

Apeks XTX50 Sidemount Regulator Set – FAQ

Is the Apeks XTX50 suitable for sidemount diving?

Yes. The XTX50 combined with the DST 5-port first stage is specifically suited to sidemount configurations. The rotating turret, fifth medium-pressure port and configurable second stage provide excellent flexibility for left and right cylinder hose routing.

Is the Apeks XTX50 suitable for cold-water diving?

Yes. The DST uses an environmentally sealed first stage designed to prevent water entering the main spring chamber, making the system particularly suitable for cold and demanding diving environments.

Why does the DST 5th port matter for sidemount?

The fifth port is positioned at the end of the rotating turret. This gives the diver additional options for routing second-stage and inflation hoses directly along the cylinder, helping create a cleaner and more streamlined sidemount configuration.

Can the XTX50 be configured left-handed?

Yes. The XTX50 incorporates Apeks' reversible design and can be converted between right and left-hand hose configurations by an appropriately trained Apeks service technician.

Can I use these regulators for technical sidemount?

Yes. The XTX50/DST combination is well suited to both recreational and technical sidemount configurations. Your complete equipment configuration should always be appropriate for your training, environment and planned dives.

Does the set include pressure gauges?

Yes. The package includes two Apeks SPGs with short high-pressure hoses for use on the left and right sidemount cylinders.

APEKS XTX50 Complete Sidemount Regulator Set