Feedthrough apparatus

A feed-through apparatus which comprises an intermediate board having at least one through-hole (thru-hole), wherein each thru-hole allows one or more cables/wires passing through from one side of the intermediate board to the opposite side, wherein each thru-hole having an elastic plug positioned inside and separating the intermediate board and the cables/wires passing through, also wherein each cable/wire comprises at least a conducting line for conducting current and an insulator layer surrounding the conductor. Inside each thru-hole, the insulator layer of the cables/wires pass through and the elastic plug positioned inside is pressed and deformed. Thus, there is no gap between the conducting line and the intermediate board through which any gas can pass.