Snap dome spring, it is a piece of PET sheet containing metal dome (dome), which is used as a switch on circuit boards such as PCB or FPC, and plays an important role between the user and the instrument. The role of tactile switches. Mainly used in membrane switches, micro switches, PCB boards, printed circuit boards, rigid boards and other products. It has several advantages such as stable contact, strong continuity, stable rebound and good hand feeling.