Berlyn Locomotive Works released these extraordinary pieces in 1998 factory painted brass, fully functional super structures in O Scale, with the ability to self propel forward and reverse on independent rails (HO scale rails will work). Gantry can traverse left to right, along with two independent cranes motors which can pick and raise or lower a load, pretty neat! The piece is independently powered by two double AA batteries and one 9 volt battery included, along with a six foot long telephone cable which plugs into the Control Tower of the Super structure for total independent operator control apart from your layout. Priced at $2500 each choose yellow or silver and make your O scale maintenance shop seems more real. Rare and very hard to find in excellent condition (please note that both double AA battery holders in both controllers were broken and have been repaired and the two locomotives and their tracks are for demonstration only and not part of this sale).