the micro trains chart says that you need the 2000 in the front (since its body mounted) and the 1128 in the rear truck for the A unit. The B unit, it says to use the 1128, since they're both truck mounted. Also, it has one for A units but has "obsolete) and i dunno what the heck that means. but it states to use 1159 for the front body mount. Hope that helps. I personally dont like how the 1128s have turned out on my trains. I always keep the Kato couplers, since they work fine with the micro trains and the accumates.