The Air Tube is a wearable and placeable item that can be bought from the Merman for 5 apiece. It can be attached to an Air Tube Anchor by left-clicking. When one piece of the Air Tube is in the player's inventory and the player is within range of their Air Tube Anchor (this depends on the amount of Air Tube attached to the Anchor), it will be shown as a black tube reaching from the Anchor to the player. The Anchor must be fueled with an Air Pump. The player will have unlimited oxygen if they are wearing the Air Helmet.