|The 168C-1 Controller was designed for use with the Magic Electrol Relay. This relay was installed in the coal tenders of just a few of Lionel's engines, such as the 201, 224, 1663 and 1666. When properly wired into a layout, you can use the button identified as Train 1 and Train 2 on the controller to change the direction of the engines in a two train operation. As an example, if your layout had a 201 switcher with a Magic Electrol Relay and a 203 switcher without the relay, the Train 1 button would control the 201 locomotive, while the Train 2 button would control the 203 locomotive. The 168C-1 Controller is often confused with the 169C-1 Controller - they are not the same.