EDA Plectrum

Its a Plectrum with EDA on it...

"noun (plural plectrums or plectra /-trə/)
a thin flat piece of plastic, tortoiseshell, or other slightly flexible material held by or worn on the fingers and used to pluck the strings of a musical instrument such as a guitar.
the mechanical part corresponding to a plectrum which plucks the strings of an instrument such as a harpsichord."