The Apollo 55000-640APO is an XP95 series optical smoke detector designed for reliable and early detection of fires in commercial and industrial environments. It operates on the light scatter principle, making it highly effective at detecting slow-burning or smouldering fires, such as those involving soft furnishings, plastics, and foam. The detector features a pulsing LED for status indication, which illuminates steadily when the detector enters an alarm state. Its sophisticated design includes an insect-resistant screen and advanced algorithms to minimize false alarms, ensuring dependable performance within a compatible fire alarm system.