K&Ks Volume Control is a non-destructive, plug-and-play addition to any single-source passive internal transducer system, like a#54105 Pure Pickup,Classic or Western FanTaStick,#54107 Twin Spot, or#44115 Big Twin.You can order it as an integrated element with any single-source passive pickup, or as an Add-On for an existing pickup. Simply unscrew the existing endpin jack, remove it from the endpin hole, and plug it into the 1/4 plug of the Volume Control Add-On. The 1/4 plug has a self-adhesive fastener, which can be secured inside the guitar. The lightweight thumbwheel control mounts with a peel-and-stick installation to the inner edge of the soundhole. Mount the new endpin jack into the endpin hole, and youre done!This passive volume control works without a battery. It does not boost the volume, but it allows you to turn the pickup signal down.It functions best when the input impedance of the device you plug your guitar into is 1 Mega Ohm (preamp/amp or mixing board-channel). If this input impedance deviates by a large amount (i.e. 100 Kilo Ohms or 10 Mega Ohms), you may experience diminished range (from full volume to off within a 1/3rd rotation) or, in extreme cases, a slight hum when the potentiometer is at middle position. This is a normal phenomenon when passive potentiometers are used with piezo based pickups. At full-on or full-off it will always be noise-free. A lot of customers use the Volume Control like an extended on/off switch.