The MXR M135 Smart Gate by Jim Dunlop is an analog noise reduction pedal designed to eliminate hiss, hum, and buzz from a guitar signal. It features three selectable modes—Hiss, Mid, and Full—which allow the user to target specific frequency ranges of noise without cutting off the sustain of held notes. The circuit utilizes dual high and low adaptive filters that respond intelligently to playing dynamics, opening instantly for transients and closing smoothly during decays. A dedicated threshold knob and a "Hi Trigger" range switch provide precise control over the gate's sensitivity for both subtle and high-gain setups. This pedal is a staple for high-gain guitarists seeking to clean up their signal chain while maintaining tonal transparency.