By Cox & Stevens Aircraft Corporation. Load adjuster for the Martin Maryland A-30 and A-30A 'Baltimore' twin-engined light bomber/reconnaissance aircraft. This looks similar to a conventional slide rule but was used to ensure the correct weight distribution throughout the airframe depending on the number of crew/equipment on board. In very good condition with sliding perspex 'curser'. Marked 'Property-Air Forces United States Army'. Despite the Baltimore being of American design it was primarily operated by the RAF in North Africa, the Middle East and the European Theatre of Operations. Stock code M27558.