Athearn Genesis G1029 HO Scale 4-6-6-4 Challenger w/Oil,N 4-6-6-4, UP #3985 Modern Model Train | Athearn,Jaap Horst History of Technology page: Rivarossi Challenger,20200728-130715-C3-Trainz-,HO RIVAROSSI #5456 4-6-6-4 Challenger UNION PACIFIC -UP 3716