This is a standard propane tank (same size commonly used for gas grills), yet is made of lightweight fiberglass composite materials, making it 30% lighter than steel propane cylinders.
These composite propane tanks are corrosion free, are easily stackable with others of the same model, and are encased in a plastic housing with handles for easy carrying.
The outer walls are translucent, allowing you to see how much propane is left in your tank.