Some components I have bought, mainly integrated circuits come with the terminals stuck in a black sponge. What is it for?
The black sponge is conductive and serves to keep all component terminals shorted, ie under the same potential, thus preventing static discharges (ESD) from damaging it. This procedure is important for protecting delicate components such as integrated CMOS and FETs, which can be easily burned by a simple finger touch at their terminals. Never remove the component of this sponge before using it and always hold the component by the body and not the terminals to avoid the static discharge of the electricity that may be accumulating in your body.
Conductive sponge
