【4-Way Roof Mount Sound Coverage】This roof-mounted car megaphone adopts a professional 4-way speaker layout, delivering uniform, wide-angle sound projection without blind spots. It achieves clear long-distance voice broadcasting, perfectly matching mobile advertising 【5 Power Output Options Commercial Vehicle Megaphone】Available in three power variants: 300W, 400W, 500W, 600W and 700W. Low power fits daily short-distance announcements, while high 600W/700W output supports loud outdoor commercial promotion for busy crowded streets and large open areas 【Bluetooth Multi-Function Voice Record】Built-in Bluetooth module for stable wireless connection with phones. Equipped with live microphone voice amplification. It also supports USB & TF card audio input and built-in musical alarm tone 【High-Fidelity Long-Distance Sound Projection】Equipped with high-power professional speaker driver unit. The sound travels far and remains clear in noisy outdoor environments, ensuring passersby can catch your promotion information easily 【Magnetic Shock-Absorbing】Comes with super strong integrated magnetic base plus shock-absorbing reinforced bracket. The firm magnetic suction fixes the speaker tightly on car roofs, no drilling required. It stays stable even during sudden braking or bumpy rough road driving without sliding or falling off