A torsional or rocker switch actuator is described that uses the torsional moment of a buckling compression spring column to rock the actuator member on a pivot. A catastrophically buckling compression column spring is used and the reaction moment which occurs as the spring buckles is applied to rock an actuator back and forth between open and closed positions with cooperating contacts beneath the actuator. A non-teasible, snap action, tactile feedback, key mechanism of extreme mechanical simplicity and high reliability is achieved.

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