USB means “Universal Serial Bus”, Chinese name is Universal Serial Bus. This is a new interface technology that has been widely used in the PC field in recent years. The USB interface has the characteristics of faster transmission speed, support for hot plugging, and connection of multiple devices. It has been widely used in various external devices. There are three types of USB interfaces: USB1.1 and USB2.0, and USB3.0 which has appeared in recent years. In theory, the transmission speed of USB1.1 can reach 12Mbps/s, while USB2.0 can reach 480Mbps/s, and the backward compatibility can be USB1.1. With the rapid development of computer hardware, more and more peripherals, keyboards, mice, modems, printers, scanners have long been known, digital cameras, MP3 players also followed. How do we access PCs through so many devices? USB was born for this. The market has a great demand for USB connectors, especially waterproof USB connector products. This is because traditional USB solutions can no longer meet the needs of consumer products. Nowadays, the density of consumer products is getting higher and higher, the transmission requirements are higher, and the demand for power supply is also mentioned, and it is required to be used in more environments. The design requirements of USB waterproof connectors can be summarized as: signal integrity, power consumption, environmental protection: 1. Signal integrity requirements The higher the signal integrity, the faster the data rate. 2. Power consumption requirements 3. Environmental protection requirements In order to provide the environmental protection that users demand, waterproof USB connectors need to have rubber seals and a seamless shell to be waterproof, these connectors should be IPX8 waterproof (according to IEC 60529), and should be durable enough to be mated and unplugged thousands of times .