CONEX - Container Express was a rigid steel reusable shipping container  8' 6" long, 6' 3" wide, and 6" 10" high, with a double door on one end. It was mounted on elevated skids to aid in fork lift handling and had lifting rings on the top four corners for dock cranes or aircraft attachment.  We often used them as easily transportable housing for command staff and medical clinics.  They would be trucked or airlifted to a site and clad in sand bags to provide small arms and shrapnel protection.