DB1SD HANDSFREE INTERCOM SUB STATION SPARE SLAVE - AIPHONE AIPHONE DB-1SDThe DB 1SD is the sub master station for the DB SERIES The Aiphone DB series intercom is designed for small apartment blocks or single residences. Up to five hands free stations can be installed in each residence. The Aiphone DB system requires a 15 volt AC power supply and is designed for use with AC operated strikes. An Aiphone IER2 call extension unit is also available which will ring when a call is made from the door station Simplified Two Wire