Fender Treble Bass Expander Tone Control.
This detented, stacked 250K / 1-Meg control enhances your tonal palatte without the use of a battery. From 0 to 5 the TBX is your standard tone control, but once you pass 5 you start to decrease the resistance which allows more bass, treble, presence and output to flow to your amp. Top quality potentiometers used on American Fender instruments. 3/8 potentiometer shafts. Mounting nut and washer included. Split shaft for compression fit knobs and solid shaft for set screw knobs