Banjo fittings

A banjo is a ring around a hollow bolt. Air runs through the bolt and along the inside of the ring to the tube. That lets the body rotate freely while the bolt stays dead tight.Use it where the tube has to move with the part, or where you only see which way it should point after tightening. On a cylinder that swings, that is the difference between a tube that follows along and a tube that splits every fortnight.