The **Apollo Discovery Open-Area Voice Alarm Devices** provide clear voice messages, alarm tones, and optional visual indication for reliable emergency notification in commercial, residential, and industrial fire alarm systems.

The **Apollo Discovery Open-Area Sounder Visual Indicator** combines audible and flashing visual alarm notification in one compact addressable device. Available in red and white models, it is suitable for commercial, healthcare, educational, residential, and industrial fire alarm applications.

The **Apollo Discovery Category O Sounder VAD Base with Isolator 45681-700** combines audible alarm notification, white-flash visual warning, detector mounting, and short-circuit isolation in one compact addressable device. Suitable for commercial, healthcare, educational, residential, and industrial applications, it helps improve occupant notification, protect the fire alarm loop, and support a cleaner installation.