If you pay attention to the specifications of the USB socket, you will notice that the wire-type USB socket is almost always sheathed, especially the USB-AF socket. This is also the wire-bonded USB socket. Different from other USB-AF female sockets, many customers come to consult and do not want this plastic or hardware casing, so as to reduce the procurement cost, and when the product is trial-produced, it will return to contact Adding sheath (plastic or hardware), they used to use the plasticizing process in the trial production. The traditional USB-AF female hardware shell has 6 stamped shrapnel, and there are openings in the shrapnel. In the middle, there will be plastic particles and powder entering the wire-bonded USB socket (which is commonly referred to as “residual glue”), which will affect the plug-and-pull performance of the USB socket. In severe cases, it will affect the product. Electrical performance. When it comes to this, everyone can use the function of the sheath of the wire-bonded USB female seat "self-evidently", yes, through the plastic or metal jacket can effectively prevent the residual glue from entering the USB socket during the plasticizing process. Internally, the reason why the wire-bonded USB busbar uses a sheath is more, because the products using the wire-wound USB busbar are generally wire-type, and must be processed. However, it does not mean that only the wire-bonded USB socket requires a sheath. Other specifications such as a plate-type or a splint type USB socket sometimes use a sheath (some products also use a plastic process), and the above is a USB mother. The main reason for the installation of sheathed wire.