Abstract: A key operable safety switch includes a housing and a switch operator that is operated by an actuator. A slot in the housing receives the actuator. A plurality of discs independently rotatably mounted on an axle, the discs each having a radial recess aligned with the slot and cam-like control grooves, form a roller. The actuator has a coded pattern or actuation portions corresponding to each disc radial recess. Insertion of the actuator engages the actuation portions with the radial recesses causing the discs to be rotated as a whole. A pin mounted to the switch operator and transversely disposed in the control grooves is axially displaced by rotation of the discs. The switch operator is displaced a predetermined stroke to actuate the switch.