Gas tank filling: Inflating is generally done from top to bottom, from high pressure to low pressure. It is recommended to chill the inflated tank in the refrigerator for 30 minutes before inflating. Warning: Operation must only be performed by professionals and in accordance with relevant national safety standards. It is strictly forbidden to inflate MAPP gas or liquefied petroleum gas into flat gas tanks or cassette gas tanks. Inflation must be conducted outdoors. Pressure release button: During the inflation process, non-gaseous contents in the tank may accumulate at the upper part of the gas tank and can be discharged through the pressure release button (for approximately 2 seconds before inflating). Note: When releasing pressure, the air valve must be closed, and the device must be installed in the correct direction. The gas from multiple unused flat gas tanks can be collected into one gas tank through this valve to enable reuse. This valve is compatible with cassette converters and other standard converters to allow gas transfer between tanks, regardless of orientation, and can be connected flexibly. The core part of the switch is made of 58 copper for durability. The gas seal uses fluoroplastic O-rings, resistant to wear, chemicals, low and high temperatures, and functions normally within -20°C to 250°C. Double O-ring design ensures sealing: one for air sealing and one to prevent leakage. Gas cylinders may vary in design, but different types of gases must not be mixed. Always use the same type of gas. A bottle collecting residual gas cannot be filled to 100%, and a newly purchased gas bottle should not be completely full either. Two effective methods: First method: A simple and practical approach—chill both the source tank and the receiving tank in the refrigerator for 20 minutes without releasing pressure, then connect immediately after removal. The cooled tank has lower pressure, while the tank at normal temperature has higher pressure, allowing high-pressure gas to naturally flow into the low-pressure tank. Second method: When no refrigerator is available outdoors, connect the gas tanks, turn off the switch, and release pressure five or six times. After releasing, open the valve to resume transfer. Pressure release alone does not ensure complete transfer. If pressure release is ineffective, combine it with shaking the source tank. Warm the upper tank by rubbing your hands around the bottom of the air outlet pipe and continuously shake it back and forth to increase internal pressure. The combination of increased pressure and periodic release allows gas to flow naturally toward the lower-pressure tank. Slightly exposing the upper residual gas tank to sunlight may also help increase pressure, but avoid prolonged exposure. Color: Grey & Red Material: Aluminum Alloy + Copper Package Contents: 1 * Camping Gas Saver Note: Light reflection and differences in display screens may cause slight variations in the color shown in the image compared to the actual item. Measurement may vary by +/- 1-3 cm.