Brand new overdrive pedal, not taken out of box only opened to take photos A recreation of an early DOD "Gray Box" 250 model effects pedal, with extra gain/grit. The JHS Pedals Overdrive Preamp effects pedal is a faithful recreation of an early version of DOD’s iconic “Gray Box” 250 pedal. It’s got two simple but powerful controls: Level and Gain. The Level control adjusts the overall output of the circuit, and lets you cut or boost the signal. The Gain control modulates the amount of gain inside the overdrive circuit—turn it up and get more clipping as it pushes the op-amp and hard clipping into overdrive. JHS has also included a slider switch so you can experiment with a different clipping arrangement. The Overdrive Preamp pedal channels all the energy of the DOD "Gray Box" 250, but with a little extra gain/grit and more unique low/mids.