It can be confusing to determine what controller your system uses, and although there are ways to determine this through the GUI, and we can walk you through this process. We have created the following cheat-sheet as a tool to help you to determine the battery required, based on visual inspection only. Below, you will see a listed model number for the controller, then an image that is similar to that model (note the location of the Ethernet ports), then a picture of the required battery. The product IDs used to purchase the batteries can vary, based on when and where the system was purchased. For simplicity, we list only one NetApp product marketing ID per battery type.