These foams fill dead space between the plate and PCB inside the keyboard. If you want a thicker, more controlled sound, foams are a great option since they fill this dead space.
PCB Foam is highly recommended. They give an extra axis of control for both the sound and feel of your keyboard!
The foam will fit any Aozora layout.
This item comes with 1 PCB foam for Aozora.
"Pumpkin" stock is foam that has been chewed by a certain feline going by the name of Pumpkin. The foam is still able to its job, though it may have extra holes or come a little mangled. The cat in the photo is Pumpkin.