The Casio PT-31 is a dark grey version of the Casio PT-30.
Year Released: 1983
Keyboard: 31 mini keys
ROM: 8 sounds, 18 rhythms
Power Consumption: 1 watt
Dimensions: 415 mm x 143 mm x 40 mm
Weight: 1.0 kg including batteries
This keyboard has built-in 0.8-watt mono speaker(s).
Batteries: AA x 5