Walthers Mainline 910-5234 HO Scale 75' Piggyback Flatcar Southern Pacific SP 510710 Millk Car The unique

The unique

Introduced in 1961

second only to P2KW-4 in number

High Downforce

Walthers Mainline 910-5234 HO Scale 75' Piggyback Flatcar Southern Pacific SP 510710 Millk Car The uniqueWalthers Mainline 910 5234 HO Scale 75' Piggyback Flatcar Southern Pacific SP 510710 Revolutionize HO Piggyback Service with WalthersMainline! Introduced in 1955, these 75' long flatcars completely changed the way railroads looked at trailer on flatcar piggyback traffic, and ushered in the intermodal age of today. Based on the original F39a class built for the Pennsylvania Truc Train service that later became the core of the Trailer Train fleet, these