The CR-2 allows the use of servo motors to drive crossing gate arms. The advantage to using servo motors instead of a Circuitron Tortoise is the ease of setup. No mechanical linkage adjustments are required since the CR-2 commands the servo motors to the positions required.

The CR-2 can drive two servo motors, one for each of two gates. The servos have a built in connector that plugs directly into the CR-2.