The MK25 EVO/S600 TITANIUM is a regulator for the Ages - literally. Ultra-light, bullet-proof and corrosion-resistant, this reg system promises a Century's worth of effortless air delivery and trouble-free service. SCUBAPRO's top regulator technology is clearly on display here. The MK25 EVO TITANIUM's first stage is machined from a solid block of titanium which does not corrode even in concentrated saltwater conditions, ensuring years of trouble-free use. It's also extremely lightweight (a full 11 ounces lighter than the brass version) and it produces a very low magnetic signature, which is why it's the regulator of choice among military divers. The MK25 EVO TITANIUM's air-balanced flow-through piston design delivers consistent and effortless airflow, regardless of depth, tank pressure, or breathing rate. With its ultra-freeze-resistant Extended Thermal Insulating System (XTIS) the MK25 EVO TITANIUM offers excellent thermal insulation by fully isolating the mechanical elements of the first stage from the cold, all without compromising breathing performance, making it an excellent choice for all water temperatures and conditions. It features a convenient swivel turret with five high-flow LP ports (high flow ports deliver about 15 percent more air than conventional LP ports). It also has an external intermediate pressure adjustment that allows technicians to maintain peak performance without the need for disassembly. The air balanced S600 TITANIUM second stage uses titanium on its exterior housing plus includes a machined titanium interior barrel for ultra-light high performance. The S600 TITANIUM delivers effortless inhalation and exhalation. It's easy to use too, with efficient user controls that include a powerful purge, an inhalation effort control knob and Venturi Initiated Vacuum Assist (VIVA) dive/pre-dive switch.