The Lionel Union Pacific No. 635 Switcher was issued uncataloged in 1965. It has a YELLOW plastic body that is painted YELLOW with RED striping and lettering on the left side, "SERVES ALL THE WEST" and on the right side, "ROAD OF The Streamliners." On the front of this engine the lettering stated in RED "NEW 7-58" and WHITE "635" and "U. P." Equipped with a two position directional unit whose control lever was adjustable from the top of the body, there is no ornamental horn or bell on this body that is mounted on a sheet metal frame that has solid non-operating couplers at both ends. Used a Type IVA motor and came with a light, but there is no headlight lens. There are no variations.

Headed up uncataloged set No. 19440.

All of the Lionel NW-2 switchers are designed to work on the tighter radius of O27 Gauge track, but they will run equally well on O Gauge track.