1. Two core plug: mainly used to transmit signals between various equipment and as an input plug for microphone input signals. According to its diameter, it can be divided into three types: 2.5mm, 3.5mm, and 6.5mm;

2. Lotus plug: mainly used for input and output plugs of circuits between audio equipment and video equipment;

3. XLR plug: mainly used for connecting microphones and amplifiers;

4. Five core socket (DIN): mainly used for connecting cassette recorders and amplifiers, it can concentrate stereo input and output signals on one socket;

5. RCA plug: RCA plug is mainly used for the transmission of video signals in equipment;

6. F, M plug: It is mainly used for the input and output of RF signals in audiovisual equipment.