Simplex 1000 Mechanical Combination Knob with Key Override and Passage FunctionSimplex 1000 Mechanical Combination Knob with Key Override and Passage Function Simplex Mechanical Pushbutton Locks eliminate problems and costs associated with issuing, controlling, and collecting keys and cards. The Simplex 1000 Series provides exterior access by combination, while allowing free egress. This mechanical lock, with knob option, eliminates the material and labor expense of battery replacements, has a single access code and is