Oceanic Zeo Second Stage SWIV with HoseDesigned for Depth. The pneumatically-balanced ZEO is an engineering marvel of precision, durability and comfort. Its durable chrome-plated marine brass metal valve delivers a phenomenal breathing experience, improves cold-water performance and helps recirculate moisture from exhalation to prevent dry mouth. The breathing adjustment gives the diver a wide range of control to precisely set airflow throughout the dive. The ZEO comes standard with an in-line hose swivel, inhalation effort control, dynamic adjustment technology dive/ pre-dive switch and a super comfortable orthodontic mouth piece featuring an inline ball swivel on the hose connection to eliminate the binding that can cause jaw fatigue.FEATURESPneumatically balanced second stage automatically maintains consistent inhalation effort throughout diveDiver adjustable inhalation effort allows the diver to control a desired level of airflow at any time.Patented Dynamic Adjustment automatically maintains inhalation effort throughout the diveAdjustable Venturi Switch (A.V.S.) for simple dive/pre-dive adjustmentInline ball swivel reduces jaw fatigueOrthodontic mouthpiece