The simple Dual second stage regulator is lightweight 6.5 oz. (183 g) offering high air flow and an easy-to-use oversized purge button. It’s first stage combination, the 15X, includes pre-oriented ports, an ACT valve which guarantees reliability and safety and a DFC system for great performance! Compact, reliable, and performance are the key words for describing this new Mares first stage. Featuring the DFC system, it meets all divers’ demands at any depth. The new valve guarantees longevity and advanced performance. The sandblasted finish chrome plated marine brass first stage regulator is a balanced diaphragm design which is inherently environmentally sealed. The diaphragm membrane transmits the pressure changes to the internal mechanism eliminating the need for the surrounding water to enter the intricate mechanism. The benefit of this type of first stage design is that none of the internal parts are exposed to contaminants such as salt, sand, chlorine or pool acids. These environmental contaminants cause corrosion and mineral deposits to form on the internal mechanism deteriorating regulator performance. The Dual 15X uses A.C.T. Advanced Coating Technology. This patented technology created to optimize performance, safety and reliability. The valve is covered with a hard Polyurethane (PU) and the sealing surface is a layered with a soft PU for a perfect seal. Tri-material (brass, soft PU and heavy-duty” PU) reaches new levels of durability. The new valve is 600% more durable than its predecessor.