BT Duet 210 Corded Telephone Classically designed and easy to use, the BT Duet has everything you need from a home telephone. It’s wall mountable to save space on your counter, has large buttons and a 10-number directory to call your favourite contacts at the touch of a button Corded Headset volume adjust: No Ringer volume adjust: Yes Digital display: No Digital phonebook: No Caller ID: No Hands-free function: No Answering machine: No Hearing aid compatible: No