The product does not make contact well with the springs on the pullman car. The springs are stainless, so they cannot be soldered to the light kit. The diodes on the board were soldered so high above the board the roof would not go on. I had to resolder them lower. The transistor was soldered in at an angle causing it to hit the roof also. After fixing these issues i finally got it working but for how long? This is not the sellers fault, it is mfg. Defects.