Acoustic (PS-900) Guitar Passive Tone Volume Control EQ Equalizer for Pickup Tuner

This equalizer helps to do passive tone and volume control of your guitar.
You can spend less time tweaking controls and more time playing.
No need of battery.
Easy to install, can be sticked near sound hole with self-adhensive, which can be reused.
Fit for most of instrument, such as guitar, ukulele, violin, etc.