MXR was a popular electric guitar effects manufacturer which began in the 1970s in New York. The original pedals manufactured were: MXR Dyna Comp (Compressor), MXR Blue Box (Analog Distortion and Octave), MXR Distortion+, MXR Envelope Filter, MXR Micro Amp, MXR Micro Chorus, MXR Stereo Chorus, MXR Phase 90, and MXR Phase 100.

Jim Dunlop currently manufactures reissues of some of the classic MXR effects pedals. They have even created their own new models in addition to the original line up, with some signature pedals such as an Eddie Van Halen Phase 90, and Flanger.