Apartment Door Buzzer <Desktop>

These use a phone line to call a resident’s designated phone number. The resident presses a specific key (typically 9 or 6 ) to trigger the door release.

The technology used depends largely on the age of the building: Apartment Door Buzzer

Common in older buildings, these use physical wiring between the lobby and each unit's wall panel. Residents use "Talk," "Listen," and "Door" buttons to communicate and unlock the entrance. These use a phone line to call a