The Apeks DS4 XTX50 regulator is the bench mark in terms of reliability and durability and will often be seen on dive boats arond the country. The DS4 first stage is the twinset set regulator of choice but provides excellent hose routing on single cylinders and stage bottles for divers who do not require a swivelling turret. The DS4 first stage is compact but delivers large volumes of gas when you need it most.
As an member of the XTX family the XTX50 second stage builds on the reputation of the ATX range. Improvements include diver changeable exhaust tee's, reversible venturi control, diver adjustable breathing resistance and the ability to change the second stage from right to left handed to suit a range of hose configurations.
The XTX50 DS4 regulator is perfect for twinsets as the ports are in the perfect location for neat and efficient hose routing whilst the breathing resistance knob and venturi contol allow an XTX50 to be used as a backup without worrying about free flows.
Diagrams explaining the technical detail of the XTX50's cracking resistant control can be found here.
DS4 first stage