Portable Air Tank: Oxygen cylinders 1.9L delivers approximately 115 breaths at 200 bar (tested at 33 ft depth). The 1.9L Portable Scuba Tank Kit Includes 1.9L air tank, regulator and diving backpack. Professional & Durable: Diving tank made of seawater-resistant 6061 aviation aluminum. Equipped with S700 regulator, safety valve, 8mm fill port, and retractable pressure gauge, easy to operate. Smooth Breathing: SRCPEG constant-pressure device ensures effortless airflow. 360° rotating joint offers flexibility in any diving position. Easy inflation: TUDIVING diving cylinders meet DOT/CE standards and can be inflated at your local dive shop. The 1.9L cylinder comes with an 8mm inflation adapter. Simply connect a standard diving cylinder to inflate it in approximately 16 seconds. Diving cylinders are also available with an air compressor for convenient inflation anytime, anywhere. Note: High-pressure manual air pumps cannot inflate the S700 Plus. Versatile Underwater Breathing Device: Working pressure: 3000Psi. Safe depth: 10 meters.Ideal for diving clubs, marine professionals, and swimming enthusiasts, this gear enhances safety and extends exploration time beneath the surface.