The DS4 first-stage regulator boasts a unique overbalanced, diaphragm design that is built for oxygen percentages between 0 – 100%. As the diver descends, its over-balancing feature allows the medium pressure gas in the hose to increase at a rate faster than the ambient, resulting in superior performance at depth. 

Additionally, 2 HP ports and 4 MP ports are angled for optimum hose routing, whilst an environmental dry system keeps water out of the main spring chamber, thus preventing ice buildup as well as keeping silt and contamination out.