In 1997, the Audi A4 gear interlock circuit diagram is shown in the figure. Welcome to reprint, information source Huaqiang Electronic Network () Crystal head is an important interface equipment in network connection. It is a kind of plastic joint which can be inserted along the fixed direction and can automatically prevent falling off. It is used for network communication. It is named "crystal head" because of its crystal like appearance. It is mainly used to connect network card port, hub, switch, telephone, etc. The two ends of each twisted pair are connected with network card and hub (or switch) by installing crystal head. Modular Plug ShenZhen Antenk Electronics Co,Ltd , https://www.antenkconn.com