For improved call handling, add a KLM. Up to 2 Key Lamp Modules can be added to an M7324 providing 48 or 96 additional programmable buttons. Use these to program features or autodial numbers, or as status indicators for designated lines and telephone sets. An expanded M7324 (with 2 klm’s) can accommodate up to 80 lines. For use with ANY existing Norstar phone system. Model number NT8B41 Also commonly referred to as a CAP (central answering position). Please note that the ac adapter is not included in this item and that this part is necessary for the item to function.