The SP-20 foot pedal adds sustain and a variety of other functions to the following Casio digital pianos and keyboards:
- CT-S200, CT-S300, LK-S250
- CTK-3500, CTK-2500, LK-256
- CT-X700, CT-X3000, CT-X5000
- CDP-S90, CDP-S100, CDP-S100, CDP-S350
- CDP-120, CDP-S130, CDP-135, CDP-220R,
- PX-S1000, PX-S3000
