The Seymour Duncan SFX-03 Twin Tube Classic is a tube driven preamp distortion guitar pedal that delivers the high-gain tones that you desire. The high-plate voltage and 100-percent vacuum tube signal path of this Seymour Duncan guitar effect pedal allow the dual triode tubes to deliver a dynamic range. Boasting two channels, this distortion guitar pedal offers wide tonal versatility - from glassy, smooth clean tones to tones with loads of crunch. When the pedal is not in use, the true bypass of the Seymour Duncan SFX-03 Twin Tube Classic allows your signal to pass unaltered. The heavy-duty steel chassis makes this Seymour Duncan guitar effect pedal durable.