Electrical switch keyboards comprise a one-piece mat made of resilient material laid in sealing engagement upon a frame within which switching elements are positioned to operate in conjunction with key portions of the mat. The mat is the uppermost layer of the keyboard and comprises the key portions connected by integral spring portions to frame positioning portions. Operation elements carried on integral extensions depending from the key portions of the mat function with the switching elements in the frame to produce switching currents upon actuation of the key portions.
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