LC1 modular ceiling speaker series are suitable for a variety of ceiling mounting environments. They can achieve excellent voice and music playback effects in indoor public broadcasting applications. The series offers five speakers with different input power, open Angle and sound reproduction effects. These include three 6 W single speaker (optional open Angle) and two high-performance 12 W and 24 W coaxial speaker actuators. They all have masks of the same size that allow the same mounting accessories to be used. These speakers are suitable for air handling sites when combined with the LC1‑MFD shell. An optional pilot sound indicator board or WLS board can be installed in the speaker frame, and an optical guide tube can be equipped to indicate the pilot sound status at the same time. Basic function voice alarm application voice alarm loudspeaker is specially designed to be used in buildings with many strict requirements on the performance of voice evacuation broadcasting system. LC1 modular ceiling speaker series are designed for voice alarm system, and have been EN 54-24 certified to comply with British BS 5839-8 standard. Protection these loudspeakers have built-in protection function to ensure that in case of fire, damage to the loudspeaker will not cause the connection circuit failure. In this way, the integrity of the system is maintained, ensuring that speakers in other locations can still communicate to people in a timely manner. In addition, these speakers can also be used in conjunction with metal flameproof enclosures to enhance the protection of cable terminals. These speakers are connected with ceramic screw terminal junction boxes, temperature fuses, and heat-resistant, high-temperature wires. All Bosch speakers are certified to meet IEC 268-5 power handling capacity (PHC) standards and can operate continuously for 100 hours at rated power. Bosch has also conducted simulated acoustic feedback exposure tests to ensure they can withstand twice the rated power in a short period of time. This ensures high reliability in extreme conditions, improves customer satisfaction, extends service life, and significantly reduces the chance of failure or performance degradation. All plastic parts meet UL 94 V0 standard for flame retardant performance. Safety compliance with EN 60065 standard * emergency compliance with BS 5839‑8 standard compliance with EN 54-24 standard compliance with EN 60849 standard UL 1480/2043 bulletproof compliance with DIN VDE 0710 part 13 standard ** * waterproof and dustproof compliance with EN 60529 IP21 standard