Abstract: A switch structure is provided for use in computer pen-based applications which can be easily adapted to perform either as a "writing" pen, an "artist" pen, or a "CAD" pen. The switch structure includes a top compression spring, an actuator, a bottom compression spring, a pair of terminals, and a cover plate which are uniquely arranged within a housing. The pair of terminals are disposed in the opposite sides of the housing. In one preferred embodiment, one end of the bottom compression spring contactly engages the pair of terminals to produce an electrical connection therebetween when the actuator is in its fully extended position. The components of the switch structure can be easily modified so as to be utilized in each of the three common pen applications, thereby reducing cost in manufacturing and assembly. The unique switch structure allows a circuit between the pair of terminals to reliably break at relatively small displacements of the actuator, with a relatively small amount of force.