The Crybaby 535Q is the Swiss Army knife of wah pedals. It provides control over the most important wah parameters, making it easy for you to create your ultimate wah tone. Select the frequency center of the effect, then dial in the frequency range to be swept by the pedal. From narrow and sharp to broad and subtle, this powerful wah will deliver it. Once you've got your sound, make sure it gets heard with the adjustable, switchable boost that can create endless sustain on any note. This is the wah pedal of choice for guitar master Joe Satriani. The 535Q offers versatility never heard before. This pedal allows the player to customize and shape the sound of the wah. By a simple turn of the "Q" dial, you can shape your wah from a narrow, sharp wah to a broad, subtle wah. Powered by the Dunlop ECB-003 or 9 volt battery. (NEW version)---Powered by the Dunlop ECB-004 or two 9 volt batteries. (OLD version) The CRYBABY 535Q also offers six new guitar wah ranges, a variable boost from 0 to +16 dB and a hard wire on/off switch. It's new custom circuitry consumes less power and eliminates unwanted distortion. Powered by the Dunlop ECB-003 or 9 volt battery. (NEW version) Powered by the Dunlop ECB-004 or two 9 volt batteries. (OLD version)