|U S Navy Calf Unit was a year end special in 1995 by Lionel. This was an add-on to the U.S. Navy NW-2 set from 1994. Very tough piece to find, being that orders were so low. This was also a first for Lionel. They had never made a dummy unit for a NW-2 diesel engine before. A must if you have the navy set. Operating headlight and operating knuckle couplers. metal chassis, handrails, wheels and axles.