AT&T 2402 Accessory Cordless Handset, Gray/Black | Requires an AT&T 2462 Expandable Phone System to Operate 2-line extension handset for your existing AT&T 2462 expandable cordless system 2.4 GHz digital spread spectrum operation Caller ID with call waiting capability 50-name and number directory and caller ID history 4-party conferencing; access to AT&T 2462 answering system