BT 4600 Additional handset: A user-friendly, big button additional DECT handset Please note that this is an additional handset and charging cradle to be purchased for use with an existing system. This handset cannot be plugged into a telephone line, and will not work without a base station (The BT 4600 main unit with base is available here). Up to 5 handsets can registered to the base of the BT 4600. Benefits of using multiple handsets include features such as: intercom, call transfer, conferencing, and shared phonebook.
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