First Stage: No swivel turret 4 medium pressure ports, 4 x 3/8" UNF 1 high pressure port, 1 x 7/16" UNF Environmentally dry sealed system Polished chrome finish Balanced for superior performance   Second Stage: Pneumatically balanced system - reduces breathing effort Heat exchanger for cold water diving Integrated Venturi Control Micro adjuster Extremely efficient exhaust valve Compact integrated exhaust 25% lighter than TX models Comfo Bite mouthpiece - for comfort and to reduce jaw fatigue