The BT 4000 Trio set of Big Button Cordless Phones without Answering Machine The BT 4000 Trio offers ease of use and extra loud volume for elderly users of landline cordless phones. The handsets are hearing aid compatible and boast a bright backlit display with extra large font, specially shaped handset for an easier grip, and big buttons for comfortable use. Further benefits of the BT 4000 include practical features including Call Blocking. Extra loud Landline calls are exceptionally clear when using the BT 4000, which is equipped with an Amplify button on the side of each handset that can be activated for an instant boost to the volume when struggling to hear. The handset volume can be easily adjusted during calls, and there is an in-built speakerphone on each handset for the convenience of talking hands-free. Block Nuisance Calls Unwanted sales calls can be a nuisance for anyone, but can be a particular concern for the elderly; the BT 4000 helps to combat these unwelcome disturbances by enabling users to prevent incoming calls from international and withheld numbers. There is also an option to block up to 10 individual numbers, and a ‘Do not Disturb’ mode to silence the ringer for all but your VIP contacts.