An electronic terminal of the type employing a card reading device mounted within the interior thereof accessible through an input port formed in a wall of the terminal. A shield formed of an elastomeric material is mounted adjacent the input port of the card reader to prevent the entrance of debris into the interior of the terminal. The shield provides at least two opposing movable overlapping flaps extending over the card reader input port. The flaps are readily flexible to allow a card to slide therebetween, and automatically flex back to an overlapping closed position when the card is withdrawn. Locator pins and mating holes are provided in said flaps to assure a consistent return to the closed and sealed position. In one embodiment, the shield is made from two half sections which may be either separated or connected via a flexible bridge. In another embodiment, end inserts are provided between said half sections which may also be separate members or attached to said half sections via corresponding flexible bridges.