The main material of the horn is the sound board adopts imported materials from Germany. The company supplies horns for many OE customers. The product quality is stable and the life is high. It solves the problem of early fatigue fracture of the sound board; the contact surface is twice. The nickel plating process solves the problem of contact rust corrosion failure of the contact; greatly improves the service life of the product; has been widely used in well-known large-scale construction machinery in China, and also has a very high quality reputation.