This Apeks Regulator Package pairs the XTX40 DIN first stage with Nitrox DS4 to the XTX50 octopus and a dedicated Apeks regulator bag, giving you a matched primary and backup air source from the same regulator family plus somewhere to keep them. The DS4 first stage uses an over-balanced diaphragm design that keeps performance consistent as you go deeper, with 4 medium-pressure ports and 1 high-pressure port angled for clean hose routing, and an environmental dry system that keeps water and contamination out of the main spring chamber while preventing ice buildup.
The XTX50 octopus shares the same pneumatically-balanced second stage approach for smooth, easy breathing, with a large 2-stage progressive purge button and a silicone exhaust valve to help clear it efficiently. A breathing effort control knob lets you desensitize the octopus when it’s stowed and not in use. Both the DS4 first stage and the XTX50 octopus use braided flexi-hoses built for coldwater use, and both can be converted from right-hand to left-hand hose routing by an Apeks Authorised Service Technician if you want the package set up differently.
Both regulators are nitrox-ready out of the box, the DS4 first stage to 100% O2 and the XTX50 octopus to EAN40, so you can move between air and enriched air without swapping parts. The DS4’s Diver Changeable Exhaust system also lets you switch between a small exhaust tee, which is what’s supplied, and a large one if you add it later. The included Apeks regulator bag rounds out the package with a dedicated place to store and carry the set between dives.
