The Lionel United States Marine Corps FA A Unit No. 221 was issued uncataloged in 1963-64. It would head up Set No. 19334 that was sold by J.C. Penny Co.
Created on an unpainted OLIVE DRAB shell with WHITE heat-stamped stripes and lettering. The shell has the front coupler pocket filled in and no ornamental horn. There is a solid non-operating coupler at the rear of the unit. The shell was mounted on a sheet metal chassis that has a single motor. This diesel has been found with both a two direction and forward only control units. The example pictured above has a two position control unit as evidenced by the control lever that is visible at the top. This engine does not have a light nor is it weighted, and it is most commonly found without the frame box. There are no variations.
This engine was issued in at least one uncataloged set that included O27 Gauge track, but it will run equally well on O Gauge track.