The super sound effect speaker series are used to clearly reproduce voice, foreground and background music in general indoor and outdoor applications. This series of speakers includes two models, providing 20 W or 50 W power amplifier capability. The material of the box body is aluminum, and the material of the top cover and bottom cover is ABS. Carbon black (D) and white (L) are available. Typical applications of these products include theme bars, music restaurants, theme parks, retail stores, video stores, conference rooms and offices, exhibition areas, demonstration environments and fitness centers. Its excellent sound reproduction capability is mainly attributed to the use of high-quality driver unit components and frequency division circuit design. Automatic reset passive components prevent high frequency units from being damaged by accidental overloads. The connecting room on the base of the device has a three-way ceramic box with screw joint, which is suitable for loop wiring. Standard with an easy-to-install and durable wall mount bracket. The mounting bracket can also be used in conjunction with LBC 1259/00 universal foot frame for temporary installation. All models are equipped with built-in 70/100v transformers, which allow easy selection of full power, 1/2 power, 1/4 power and 1/8 power rate through taps on the primary coil. These taps are connected to the transformer knob switch in the box base connection chamber, as this user can set the output power very easily. Low resistance connections are also provided on the transformer switch. Basic function voice alarm these voice alarm speakers are specially designed to be used in buildings that have many strict requirements on the performance of public broadcast systems. LB1 UMx0E‑x is designed for voice alarm system, and has been certified by EN 54-24 to meet BS 5839-8 and EN 60849 standards. Protective loudspeaker has built-in protection function to ensure that in case of fire, the damage of loudspeaker will not cause the failure of its connection circuit. In this way, the integrity of the system is maintained, ensuring that speakers in other areas can still communicate to people in a timely manner. The wiring and safety loudspeaker is equipped with ceramic terminal junction box, hot-melt fuse and heat-resistant high-temperature conductor. An optional circuit/speaker monitor board can be installed inside the speaker box. All Bosch loudspeakers are certified to meet IEC 268-5 power amplifier (PHC) standards and can operate continuously for 100 hours at rated power. Bosch has also conducted simulated acoustic feedback exposure tests to ensure speakers can withstand twice the rated power in a short time. This ensures high reliability in extreme conditions, improves customer satisfaction, extends service life, and significantly reduces the chance of failure or performance degradation. Safety meets EN 60065 standard, emergency meets EN 54-24 standard, BS 5839‑8/EN 60849 standard, waterproof and dustproof, EN 60529 and IP 65 standard