Feature: 1. The mouthpiece is made of food‑grade organic silicone, which is non‑toxic and tasteless, and is safer to use. 2. With up pressure relief valve, easy to operate, just press the up to release the gas in the bottle. 3. Waterproof luminous pressure gauge, stylish and beautiful, suitable for use in dark environments. 4. Help you breathe freely underwater, this is a practical and reliable diving equipment. 5. 0.5L capacity oxygen tank is more convenient, it is easy for beginners to dive, and the underwater breathing time can up to 5-10 minutes. Specification: Item Type: Diving Oxygen Tank SetMaterial: Aluminum Alloy + Stainless Steel + SiliconeSize: Approx. 290x60mm/11.4x2.4in Weight: Approx. 4850g/171.1oz Breathe underwater for about 5-10 minutes Maximum Pressure 30000SI/200BAR/20MPA Number of breaths: about 170 times calculated as 0.5 LLTERS per breath Available time is more than 10 minutes (deep sea within 10m) Surface Treatment Process: Hard oxidation and spraying, seawater corrosion resistance for more than 500 hours Duration of use in different water layers: 1-3M, about 8-10 minutes 3-7M, about 6-8 minutes 7-10M, about 5-6 minutesInflation Method: High-pressure air cylinder, electric air pump, scuba adapter. Package List: 1 x Oxygen Tank (Without Gas)1 x Breathing Mouth1 x Rope1 x Spring Hose1 x Handle1 x Pump1 x Storage Bag 1 x Pressure Gauge1 x Instruction1 x Manual 1 Bag x Accessory 1 x Strap1 x Scuba Adapter Note: When the oxygen tank is inflated, the pressure value cannot exceed 3000PSI or 200BAR. Ship without gas.