BOSS CP-1X Compressor Pedal Features: Compression pedal featuring BOSS's Multi-Dimensional Processing Easy-to-read gain reduction indicator Classic BOSS comp pedal control layout 18-volt internal electronics offers high-headroom performance Works with optional 9-volt BOSS power supply Tech Specs Pedal Type: Compressor Inputs: 1 x 1/4" Outputs: 1 x 1/4" Bypass Switching: Buffered Power Source: 9V DC power supply required (sold separately)