Portable Scuba Tank: Offers 6-12 minutes of submersion time with 0.5L oxygen cylinders. Suitable for a range of underwater depths, providing approximately 66 breaths for surface breathing. Innovative Bottle Design: Equipped with a luminous gauge for visibility up to 80 meters deep, a pressure relief valve for easy air venting, and a multi-filter air system for pure breathing. Safety and Customization: Features a professional-grade dust cap for nozzle protection. Offers three inflation options for different scenarios, with a maximum inflation pressure of 3000PSI/200BAR/20MPA. Durable Construction: Crafted from aluminum alloy with a multi-layer, corrosion-resistant coating. Undergoes an automatic mirror layer spray process for enhanced durability. Complete Diving Kit & Usage Instructions: Alongside the oxygen cylinders, the package includes 1 manual pump, 1 refill adapter, 2 ropes, 2 diving goggles, 1 carry bag, 2 dive storage bags, and 2 flashlights. For safety, maintain cylinder pressure below 20 MPa (200BAR/3000PSI). Before air travel, release the pressure and separate the breathing valve from the bottle. Portable Scuba Oxygen Bottle: Can be submerged for about 5~10 minutes, can be used for adult surface breathing about 66 mouthfuls of air, different underwater depths, the available time also varies.