Overdrive Effects Pedal, Accel Express OD Vintage Tube Screamer Overdrive Pedal that sounds great at an unbelievable price! Nice range of tonal variations. Uses the classic JRC4558 chip,True bypass design. Controls: Volume, Tone, Drive. Toggle Switch: Normal/Bright/Warm. Power Source: 9v battery, DC9v adapter or 9v power supply (not included) For video sound demo's; Search "Accel Express Overdrive pedal" on Youtube