Liquid Oxygen Systems

Pros: When oxygen is in a cold state, it turns to liquid. This liquid allows for a greater amount of oxygen to be placed in a tank and weigh less than a compressed oxygen tank. As with the compressed oxygen, it can be filled into smaller units for portability purposes.

Cons: There are some disadvantages of these units of which to be aware. For one, it is more expensive than compressed oxygen and does not have as long of a shelf life as it will evaporate. Also, you will not be able to take liquid oxygen tanks on a plane.