Locomotive 35012 entered service with the Southern Railway in January 1945 with the palindromic locomotive 'number' 21C12. It would gain its more conventional number under BR before being rebuilt by the nationalised operator in February 1957, making it one of the first examples to be rebuilt. The locomotive would go on to serve under BR, mainly on the former Southern region before being withdrawn in April 1967. United States Lines would be scrapped in Newport shortly after.
The Hornby Merchant Navy is fitted with a powerful five pole motor and a large flywheel providing excellent performance. The locomotive if fitted with a fully detailed cab, tender pickups, NEM pockets front and rear and a 21 pin decoder socket.