Boss XS-1 Poly ShifterThe XS 1 Poly Shifter delivers instant retuning in a convenient, compact footprint. Driven by advanced BOSS algorithms years in the making, this magical pedal transforms the overall pitch while maintaining your instruments true character. You get speedy tracking, crystal clear response, and zero compromise in tonewhether shifting down, simulating a capo, or using extreme octave jumps for effect. The versatile XS 1 unlocks a new level of performance