The Slow Engine cuts off the attack of each note and produces and effect like rolling up the volume knob or that of a bowed instrument. With the Attack and Sense knobs you can control the amount of the effect and tailor it to your sound.
Please note the all Mooer micro series pedals must be powered by a 9V DC adapter (not supplied) as they’re so economical on pedal board space you can’t even fit a battery in!