The Casio keybed was split into 4 zones and each zone used a different hammer. The group numbers 1 through 4 are stamped on the metal part of the hammer. These hammers fit the following Casio models. Be sure to select the group you need from the drop down box.

CASIO AP200
CASIO AP400
CASIO CDP100
CASIO PX110
CASIO PX120
CASIO PX200
CASIO PX310
CASIO PX320
CASIO PX700
CASIO PX720
CASIO PX720C
CASIO PX800