Clean boost and a distortion circuit—like 2 effects in 1 box.
The Vexter Box of Rock is a silkscreened version of ZVex's first distortion pedal, highly specialized to simulate the "everything on 10" sound of a classic Marshall amplifier. Use your guitar's volume control to adjust the amount of distortion you need, all the way down to very clean and clear with most drive settings. The silkscreened ZVex Box has one "Distortron Engine" stomp switch—that's no typo, but what Mr. Vex himself calls his distortion circuit. The Box of Rock also contains an extremely high-headroom, unity-to-50X gain booster with nominal input impedance and low hiss.