In the words of Boss:

Offering a universe of rich, analog-inspired polyphonic tones in a small footprint, the SY-200 synthesize effects pedal makes it simple to weave BOSSs expressive guitar and bass synth technology into all of your musical journeys. Building on the fun, instantly gratifying experience of the acclaimed SY-1, this blue inspiration machine features an expanded sound set, more tone-shaping possibilities and 128 memories for storing your sonic creations. Two onboard footswitches provide deep real-time performance control, and you can take things even further with external footswitches, an expression pedal and MIDI.