Exquisite metal shell --- Exquisite metal shell, exquisite workmanship, drop resistance, not easy to wear, reliable quality, elegant and durable, long service life, chrome honeycomb cover can prevent deposits from entering while driving and prolonging the service life Waterproof design --- Loud and clear sound of 992B, which can make the sound clear even in noisy streets, waterproof design, reliable use Simple Installation --- Installation is convenient and simple, does not require complex operation steps, does not require complex tools, is convenient to use, and does not require modification, but it is always recommended to use professional installation Standard Specifications --- Manufactured in accordance with standard specifications, strictly follow factory quality control, precise manufacturing and stable performance, professional performance, reliable quality, very suitable po ur you