The Mares Instinct 15X Regulator is a top-performing choice for the traveling diver. Its lightweight and compact design, combined with the hydrodynamic instinct 2nd stage, ensures high performance without added weight. The balanced diaphragm 1st stage provides environmental sealing for optimal functionality and the Superflex Hose enhances comfort. 1st Stage Balanced Diaphragm Four 3/8" Threaded LP Ports Two 7/16" ThreadedHP Ports 2nd Stage Downstream Demand Valve