these DC locomotives are extrnally identical to their AC counter parts but have a can motor and are a 1/3 of the cost. a simple way to ad a tab & slot coupler to the tender, only takes a minute and will last virtually forever. swing the knuckle out for lionel or the tab & slot for marx. this will couple with lionel, marx tab & slot, marx plastic knuckle and marx plastic tilt. really expands the use of these locomotives...