What the C-slot designation means for fit
The SME-10M-ZS-24V-E-2,5-L-OE: The 'C-slot' in the model tells you this switch mounts into the T-slot or C-slot profile of FESTO pneumatic actuators — typically cylinders or linear slides. It is not a general-purpose proximity switch for flat surfaces; it is specifically shaped to snap into the extrusion groove of a FESTO actuator. If your BOM calls for a switch that fits a C-slot profile, this is the direct fit. If you are replacing a switch on a non-FESTO actuator, you will need to verify the slot geometry first.