ITEM NAME:Universal General Guitar Acoustic Clip On Pickup Piezo Contact Microphone B D3S5 Universal General Guitar Acoustic Clip On Pickup Piezo Contact Microphone B D3S5 Built-in vibration sensor. The clip is built-in vibration sensor which could make a response to vibrations,then transform them to electric signals and deliver them through cable to the tuner. Standard jack dimension. Jack: 6mm(appo) Cable length: 82cm Colour:black It is especially designed for guitar tuning. Using it is easy,just clip it to the position where vibration is more obvious on the instruments. Package included : 1xUniversal General Guitar Clip-line Pickup (Guitar Tuner Not Included) Note:Light shooting 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.