The Bosch high efficiency horn speaker provides superior voice playback and sound transmission efficiency and is suitable for outdoor applications. They are ideal for sports fields, parks, fairs, factories and swimming pools. The LBC 3484/00 is a circular 50 W horn speaker with a diameter of 490 mm (19.6 inches). They are made of aluminum. The edge is covered with PVC profiles to prevent damage to horn speakers due to impact. The color of the loudspeaker is pale gray (RAL 7035), with waterproof and dustproof functions. Voice alarm speaker LBC 3484/00 is designed for voice alarm system and conforms to emergency standard. The horn speaker has built-in protection. In case of fire, this protection function can ensure that the damage to the loudspeaker will not lead to the circuit connected to it. In this way, the integrity of the system is maintained, ensuring that speakers in other areas can still communicate with people in a timely manner. The horn loudspeaker is equipped with ceramic junction box, temperature fuse and heat - resistant high - temperature wire. Optional circuit/speaker monitoring board can be installed internally. The rear cover of the basic function horn speaker is made of ABS flame retardant material (up to UL 94 V0 level). The connecting cable is wired through the cable seal plug of the back cover (PG 13.5). A second cable access hole (covered in standard equipment) is also provided on the back cover for loop connection. These integrated horn speakers can also provide a single horn speaker housing and exciter, allowing users to install any horn speaker housing and actuator combinations as they wish. For type Numbers, see ordering information. 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 of the speaker under extreme conditions, improves customer satisfaction, extends service life, and significantly reduces the probability of failure or performance degradation. Security in accordance with EN 60065 standard waterproof and dustproof conform to IEC 60529 and IP 65 standard emergency in accordance with BS 5839 ‑ eight/EN 60849 standard wind in NEN, 6702:2007 + A1:2008, Bft11 certification European CE standard area easy installation/configuration of power set horn speaker comes with screw terminals (including earthing terminal) tee connection box. The three jumper joints on the matching transformer are used to select rated full power, half power, or quarter power (increment 3 dB).