Abstract: Plug-through electrical transient voltage surge suppression for watt-hour meters and downstream electrical equipment. A circuit board is configured to fit about the power terminals of such a meter and are supported by the terminals or by a plug-and-jack adapter interposed between the meter and its socket in a grounded utility box or panel. The circuit board conveniently and effectively connects a plurality of varistors between the power terminals and an external ground, enabling the varistors to clip voltage surges unassisted and to shunt resulting surge currents to ground, thereby protecting both the meter and powered downstream electrical equipment from possible surge damage. Each varistor is preferably sandwiched contiguously between the grounding plate and respective powered conductive surface layers on the board, or the varistors may be mounted on pairs of leads connected between ground and powered leads and preferably bendable to parallel the varistors to the board and grounding plate.