A reusable container which provides flame and thermal protection for shipping hazardous materials such as cylinders containing compressed gas has a flame resistant reinforced outer shell having a bottom section hingedly coupled to a top section. A first inner layer of thermal insulating material is fitted into the top and bottom sections of the outer shell. An optional second inner layer of shock absorbing material with thermal insulating properties is fitted next to the first inner layer and configured to contact and conform to surface sections of the compressed gas cylinder. An interior liner comprised of a durable liner constructed of fabric or molded heat-resistant plastic.