Sizes A, 8, J, K, M and T cylinders are intended for transportation and storage of such gases as oxygen, nitrogen, helium, argon, hydrogen, ethane and monochlorotrinuoromethane. Size T is commercially known as a trailer tube and is used individually or group mounted in a rack to form a transport trailer. Size C is intended for oxygen for use in submarine welding and cutting outfits, Sizes D and E are intended to serve principally as containers for medical gases. These cylinders are intended also for other gases when equipped with suitable valves and properly painted. Medical gases which may be carried in these cylinders include oxygen, nitrous oxide, helium, carbon dioxide, ethylene and cyclopropane. Size f is intended for oxygen for use in pack type emergency cutting, Sizes G, H, I and L are intended principally for use as components of carbon dioxide type fire extinguisher.