Abstract: An image forming device, a customer replaceable unit host device in communication with the image forming device, and controlling methods thereof. The image forming device includes a recording material storage medium, a customer replaceable unit memory (CRUM) associated with the recording material storage medium to store usage information for replaceable units installed in the image forming device, and a first controller to collect the replaceable unit usage information, to control the replaceable unit usage information to be stored in the CRUM, and to transmit the replaceable unit usage information to the customer replaceable unit host device. In this manner, a plurality of image forming devices can be collectively managed in an efficient manner.