This Con-Cor Unpowered PB1 with an installed sound decoder makes it easy to add authentic Alco PA sound to your locomotive consists. The installed sound-only decoder with speaker operates on both DCC and DC layouts. When running on DCC you have full control of the sound package - simply give the locomotive your choice of address and operate it behind your DCC PA1 diesels. On DC systems the preprogrammed sounds begin with a locomotive startup sequence when track power is turned on and the sounds increase as more voltage is applied. This model matches Con-Cor Alco PA1 and PB1 diesels but can also be used in consists with Alco PA1 locomotives (and other diesels) made by other manufacturers. Other features of this non-motorized diesel include fine decoration, metal wheels and magnetic knuckle couplers. All sound-equipped unpowered Alco PB1 diesels come with black trucks.