Perhaps surprising to some, what are shown in the photo are indeed HO models and the photo certainly could date from 1942 . The locomotive is clearly identifiable as a pre-war two-rail Gilbert (American Flyer) HO Hudson. A dead give away are the distinctly over-sized rivets on the tender, the makers of the OO Lionel Hudson having exhibited decidedly more attention to scale representation on their model. Gilbert produced essentially the only ready-to-run large HO road locomotive of wide availability prior to the coming of WWII, the locomotive being extremely popular among hobbyists of the period, together with the Mantua and Varney 0-4-0 yard goats. The pre-war version of the engine operated on 6-volts, while the post-war example, hugely popular during the model railroading craze of the 1950's, was a 12-volt item like today's. Likewise, the caboose shown is recognizable as a Gilbert NE-type model. Most of the others are also likely Gilbert products of the immediate pre-war era.