Cylinders
Scuba Cylinder Markings
cylinder capacity stamp
Scuba Cylinder Markings
All cylinders have important specifications stamped around the top of the tank. The location and format may vary between manufacturer, but with practice you'll learn to recognize key specifications and what they mean.

Capacity
Most aluminum cylinders have their capacity stamped on the cylinder. This is not a required specification, and very few steel tanks have a capacity stamp.