D-sub connectors in China are usually divided into DB, HDB, DP, HDP, DR and HDR. D-sub connector, also known as D-sub miniatures; The foreign names are d sub-miniature, d-sub connector, d-type connector, db connector, VGA port (d-sub 15pin), which are commonly used electrical connectors in computers. D-sub connector has parallel connector pin arrangement and is surrounded by metal shield. The shielding end is short, similar to the English letter D.

The connector has a D-shaped metal shell. This not only provides mechanical strength for the connector, but also provides some limited screening: the metal shell of the plug and socket contact to provide screening. In addition, panel-mounted connectors are usually fixed to the panel using nuts with additional threads that allow the mating connectors to be fixed thereto to prevent them from loosening. In addition, certain connectors can provide a rear shell with shielding and can be connected to a cable screen, or if they are plastic, they can provide protection.