A metal dome (pot) is used as the contact surface of the upper circuit button. The button life is more than one million times, the hand feel is good, the intensity is even, and it can still be used normally under high temperature environment. This product is mainly used for the function keyboard of industrial control equipment. Haiwen's products can be designed according to customer needs, such as button content, color, effect, etc. The panel is screen printed with Ketutai F150 frosted PET, and the window is treated with UV window liquid to make it transparent and beautiful. The circuit is Edgson Acheson silver paste ED-820B printed circuit, the resistance is small, long life, the connection is DuPont socket. 3M468 tape is used on the back.