The Owl Micro wireless electricity monitor allows you to take control of your electrical usage and get real time feedback on how much your electricity costs you. The Owl Micro is easy to install and use and details the actual savings from turning off appliances, lights and more. Simply clip the sensors around both hot phases of the main electrical supply cables in your homes electrical panel, then plug the wires into the wireless transmitter that sends data to the remote display unit, which can be used as far as 100 feet away. Dimensions L x W x H (in.): 2 3/4 x 7 1/2 x 8 1/4, Color: White, Display Type: LCD, Battery Type: AAA, Battery Included: Yes, Mounting Hardware Included: Yes Calculates costs per hour and total costs Measures amps used, calculates usage based on system voltage