Electro-Harmonix Black Finger Tube Compression PedalDual tube magic! Using the same professional grade techniques as the most revered, vintage, high end studio compressors, the Black Finger delivers truly professional performance compression. Unlike other "tube hyped" products on the market, which use 9 to 50 volts, the Black Finger's toroidal transformer allows for a full 300 volts of swing, preserving the attack while providing the warmest compression imaginable. Fantastic sustain, and a must for any