A flexible, pressurizable signal processing device such as a keyboard device (10) is made of resilient layers (12, 14) of plastic material having a common periphery (15), with molded keys (16) which are deformable when pressed so as to send a signal via a conduit (24) to an electrical device (26). The keys are arranged with a flexible electrical circuit (22) thereattached and with interconnected inflation channels (13) therebetween, such that when a key is depressed an associated conductive trace (20) establishes a proper complete circuit.
