Synthrotek Ratatak Distortion Kit - Pcb-Mount 4 controls - Volume, Drive, Filter, and R-Tone - to customize your tone. Volume sets the output level, Drive lets you determine the signal gain, Filter dials in the high frequency response, and R-Tone turns up your bass frequencies from clean to fuzzy grit. DIP Switch Diode Clipping - On-board 4PST DIP Switch selects between 4 different clipping diodes to drastically alter your sound. Turn on the stock version 1N4148s, LEDs, Germanium diodes, or none at all with flick of a little switch. Tons of tweak! PCB is designed the original RAT tone IC, the LM308 single op amp, for the vintage tone. The updated version of the RAT line of pedals uses an inferior-sounding OP07DP op amp IC. Get the vintage tone! 3PDT switch layout allows for an easy wiring job, with true bypass switching and LED indicator to give you a visual cue when your RAT Distortion Pedal Clone circuit is engaged and using power Dual power supplies (9V Battery and +9VDC =&gt;200mA Center Negative DC Adapter Power Supplies) allow you to have the battery as backup or as the main power