First Stage. DFC system (patented) Dynamic Flow Control system controls airflow for consistent breathability at all depths by maintaining the intermediate first stage working pressure. The first stage has 6 ports; 4 low-pressure and 2 high-pressure. Comfort grip knob on first stage yoke. Balanced diaphragm designed for consistent performance at depth. Port system optimally pre-oriented. Body is made of high-strength nickel and chrome-plated brass with a matte satin-finish exterior. Second Stage. Dual-material construction, exceptionally lightweight (patent pending) with DPD (Dive/Pre-Dive) system for maximum practicality of use (patent pending). Integrated VAD by-pass system (patented) for high performance and natural, comfortable breathing at all depths. Cover plate with mesh-grid design (patented). CE UNI-EN 250 Certification.