The Union Pacific Big Boy 4-8-8-4 articulated locomotives are among the largest steam locomotives ever built. Built in 1942 and donated for display on retirement in 1959 Union Pacific required Bog Boy 4014 in 2013, adding the engine to the railroads' heritage steam programme and returning the giant locomotive to service in 2019.
This N gauge model has been under development by Kato's design team for over three years, culminating in the creation of a highly detailed model engineered to balance the distribution of weight across two mechanisms hidden beneath the boiler, each with its own coreless motor drive and synchronized with each other to achieve incredible smooth motion along with a powerful pulling capacity of two engines.