During the same time, the United States Army started to combine items of uniform size, lashing them onto a pallet, unitizing cargo to speed the loading and unloading of transport ships. In 1947 the Transportation Corps developed the "Transporter", a rigid, corrugated steel container with a carrying capacity, for shipping household goods of officers in the field. It was long, , and " high, with double doors on one end, mounted on skids, and had lifting rings on the top four corners. During the Korean War the Transporter was evaluated for handling sensitive military equipment and, proving effective, was approved for broader use. Theft of material and damage to wooden crates convinced the army that steel containers were needed.