Abstract: A container such as a case or box is provided with at least one fitting that has an adjustable arm provided with a connecting opening for receiving a connecting part of a motor vehicle. An insertion opening that is size-adjustable opens into the connecting opening. The connecting opening is defined by a hook of the adjustable arm and by a counter member that is adjustable relative to the hook. The hook is provided at the free end of a rod of the adjustable arm and the counter member is provided on a free end of a sleeve of the adjustable arm movable on the rod.