Compare the Simplex 4099-9004, 4099-9006, and 2099-9756 manual pull stations, including their addressable or conventional system type, single-action or double-action operation, key features, applications, installation requirements, and maintenance considerations.

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.