This is a set of 5 chromatic notes that can be added to the MPP-8. When a push pump is pressed by hand, the air inside the pump is pushed out and the reed sounds.

The MPP-8 added to the MPP-5 make 1 octave chromatic 13 note set.

Place it on a desk or flat surface and press or strike the top middle center of the instrument to play. Press slowly to produce a long sound, press quickly to produce a short sound, press strongly to produce a loud sound, and press lightly to produce a soft sound.