Dunlop positioned the MXR FET Driver (M264-U) as a compact overdrive pedal designed to replicate the character of an overdriven tube amplifier through field-effect transistor circuitry. It occupied a place in the MXR effects line as a tone-shaping drive unit aimed at players seeking amplifier-style saturation from a pedal platform.

The FET Driver featured Hi and Lo boost/cut controls for tonal fine-tuning across the frequency spectrum. It operated on a 9-volt DC power supply, drew 25 mA of current, and specified a noise floor of -88 dBV — a relatively low figure for a drive pedal of its class. Input impedance was rated at 1 MΩ and output impedance at 15 kΩ, figures relevant when considering signal chain placement. The unit employed true hardwire bypass, meaning the input signal routes directly to the output with the effect disengaged.

Owners working on setup, repair, or integration into an existing signal chain should consult a qualified guitar technician, particularly when matching impedances to adjacent devices or tracing any noise-floor concerns.