The ultra-long flexible two-layer FPC (Flexible Printed Circuit) board is a type of electronic circuit board with the characteristics of flexibility and bendability. It is usually used in electronic products that require bending or deformation, such as mobile phones, tablets, televisions, automotive electronics and so on. The two layers of circuits on this FPC board are connected by flexible insulating materials, enabling it to adapt to complex shapes and structures. Meanwhile, it also has the advantages of high efficiency, flexibility, portability and reliability.