Circuitron #800-5401 AR-2 Automatic Point-to-Point Reversing Circuit with Adjustable Delay for DC Product Information Same as AR-1 but with adjustable delay to hold train at sensor before reversing. Adjustable delay from one second to over one minute. Can be connected to pushbutton or DT-4 to permit stops and delays without reversing. Requires 12-18V DC power supply. Constructed on 3 x 3" printed circuit board.