Descriptions: 1.This is a an audio common ground isolator module. 2.It is effective for the noise caused by the common ground for the audio source and the receiving device. Specification: Name:Audio common ground isolator Colour:As shown Material:PCB Size:45 x 30 x 20mm Package Contents: 6 x Audio Stereo Isolator 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.