Abstract: A sealed enclosure means for an electrical switching array and a method of preparing such an enclosure, with the switching array employing a plurality of generally rigid terminal contact pins which extend outwardly from a wall of the enclosure. The wall through which the terminal contact pins extend has a plurality of slots formed therein, with the slots having contact pin engaging edges. The material from which the wall is fabricated through which the terminal contact pins extend is generally resilient, and the slots which are formed therein to receive the contact pins have a width which is less than the pin thickness so as to cause the slot edges to temporarily form a lip seal about the surface of the pin. The terminal contact pins are then heated so as to cause the thermoplastic resilient material to flow to form a seal about the periphery of the contact pin.