Boss FB-2 Feedbacker/Booster Pedal.
From Boss: "Wide tonal variety, from flat, clean boost to powerful mid-boost and bright, clear treble boost. Boost characteristics can be changed continuously and smoothly from one knob. Responds expressively and accurately to picking nuances, even at high-boost settings. Versatile tone, simple operation, and low noise. Advanced Feedback function provides smooth and natural amp feedback."
Deposit required, refunded upon return.