Ethylene-vinyl acetate (EVA) case foam special cut for ELISE Layout keyboards. Case foam is patterned after the contour of Prime Keyboard's v1 Prime_E PCB, and fits into the Prime_Elise case.
Foam layer underneath the PCB (between the PCB and the bottom case).
The foam doesn't silence typing sound, rather it changes "thocky" keyboard sound profile, and fills empty gaps which makes typing sound less hollow..
