The CU-200 Control Box is an optional add-on that gives you additional functionality for your SQFlex pumping system. It has an On-Off switch, Power Consumption Meter, Diagnostics, and a place to mount the Float Switch wires. The CU-200 box makes it possible for you to run up to 1600 feet of 18 ga, 2 conductor wire to your float switch. That's because instead of routing all the pump current through the float switch, the circuitry in the box is designed to let the Float Switch control the pump with only microamperes of signal. It can mount under the solar array or any convenient spot that's out of direct sun.