Kato USA Model Train Products Gunderson MAXI-I TTX #751193 Double Stack Car Set with Maersk 40' Containers, 5-Unit Set Steel-plastic compound wells give heft and make operation possible even when running empty Included 10 x magnetic Maersk 40' containers which can be removed and swapped with other intermodal cars Articulated wells have easy-to-connect/disconnect clips which make transition from storage to operation and back a snap