The MXR ZW90 Zakk Wylde Phase is a signature phaser effects pedal designed in collaboration with guitarist Zakk Wylde. It provides classic analog phaser modulation using a single Rate knob to control the sweep speed, delivering everything from slow, warm sweeps to more intense, rapid modulation effects. This pedal features a rugged stompbox design suitable for live and studio use and is built to add dimension, texture, and dynamic movement to guitar (and even bass/keys) tones beloved in rock and metal genres.