Local function: Reduce the audio signal output by the circuit to a small size that can be input to devices with microphone interfaces; What is line output, such as mobile phones, MP3 players, computers, CD players, , and electronic instruments (electric guitars, hair dryers, saxophones, electronic pianos, electronic drums, etc.)? The signal strength output by these electronic products is about 0.3vrms to 2vrms; The microphone input port requires a voltage range of 0.01V-0.1V. If the output signal of the circuit is input, excessive signal can cause serious distortion. This machine can reduce the signal to a suitable size, so that some audio devices can be input to the sound card or speaker interface, causing them to produce reverberation effect. It is suitable for some music playing friends to live stream and record videos. cable type:6.5 male to male cable Attenuation: -40dB~-15dB adjustable Colour:Black Material:plastic Size:6.5x5.3x2.4cm Package Contents: 1 x Audio Passive Attenuator 1 x cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.