Very easy to install and sounded good through several different amps. Plug Dia. : 6.35mm/0.25 inch; Cable Length(.) : 35cm/ 13.78 inch. Suitable for Guitar Violin Ukulele Mandolin Banjo Guitar. With the advantage of being to interfering external sounds and not be influenced by sound reflections from nearby objects. Material:Metal COLOR:black The sound pickup is high-quality 27mm Piezoelectric ceramic disc ducer It is very large and can collect a range of sound in case you are not sure where are the best parts of the sounds. This is a pre-wired, pre-soldered piezo and jack harness which easy . All you have to do is to attach the piezo in or on your build, drill a hole and mount the jack. Then you're done! Fit for most string music inst ents such as Guitar Mandolin Guitar Violin Ukulele Banjo, etc. Installation instruction: 1 Take the plastic film down from the back of ducer to expose the adhesive 2 Place the ducer through the sound hole to the lower part of the front body where the guitar produces the best response 3 Drill a hole from inside the body, loosen -pin jack nut, insert it to the hole and tighten the nut The above procedures depend on different inst ents. Cable long : 32cm Plug Dia: 6.35mm/0.25 inch Package included: 1x pickup 4x gasket 1x knob 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.