Features: -The 90 degree elbow design helps gas flow smoothly to smaller cylinders. -Equipped with an on-off control valve to minimize gas leakage during cylinder connection, allowing safe and controlled refilling. -With color gauge, it can quickly evaluate the remaining gas in the large tank to avoid insufficient gas level during the refilling process. -Made of solid brass material, it has stable performance, ensures excellent sealing and long service life. -The adapter is used to fill a small tank of propane from a large tank. It is perfect for barbecue, camping, party, heating and other outdoor activities. How to refill propane gas? .