Our NEW Carbon Fiber Cylinders manufactured by Cobham Mission Systems (formally doing business as Carleton) are built around DOT specifications and have a working pressure of 2216 psig. These cylinders are lightweight, composite cylinders consisting of an aluminum alloy inner shell, with a total over wrap of carbon fiber, fiberglass and an epoxy resin. They are rated for 30 minutes in duration. Your choice of make of valve assembly. These cylinders are manufactured to the same specifications and standards as our leading new SCBA competitors.