Valcom Speaker with Universal Controller is a door phone and door opener controller. Features: Provides voice communication between your telephone system and the door phone speaker Controls remote door unlocking (with optional customer-supplied and customer-installed electromechanical strikeplate) Has door ajar/detect notification capability when used with a customer-supplied and customer-installed door switch Includes controller and volume control door speaker Push button activation Stainless steel faceplate and tamper-proof screws Weather-resistant enclosure for indoor/outdoor use Mounts to virtually any surface or flush mount