Wm. K. Walthers, Inc. / PROTO  1000 HO Scale Diesel EMD GP15-1 Powered Conrail #1685 DCC-ready - accepts 9-pin plug 14:1 gear ratio for easy multiple-unit operations Helical gears for ultra-quiet and smooth operation Five-pole, skew-wound can motor Proto MAX(TM) metal knuckle couplers