Infinite Oxygen Supply
An Infinite Oxygen Supply is a Liquid Oxygen Canister which never runs out! It is a Creative Mode-only item, it cannot be crafted.
The Infinite Oxygen Supply can be used to provide infinite amounts of oxygen to any machine which uses oxygen, for example the Oxygen Distributor or Oxygen Sealer. This can be a great way to test your builds. Just place the item in the oxygen item slot in the machine, and it should start working.
Note: it's a canister, not a tank. Canisters, like the Liquid Oxygen Canister, are containers for tranporting oxygen and placing it into machines - similar to a Water Bucket in vanilla Minecraft. Tanks are for the player to wear as part of a life support system. A player cannot wear an Infinite Oxygen Supply.
Use in a crafting grid with a Light Oxygen Tank, Medium Oxygen Tank or Heavy Oxygen Tank, and the Infinite Oxygen Supply will fill the tank if it can. The crafting result will be the filled tank, and the Infinite Oxygen Supply item will be returned to your inventory.