When the beam path is interrupted, the safety outputs switch off, stopping the guarded machine. This class of device is typically deployed on assembly lines, press brakes, packaging machinery, and robotic cells where personnel access to a hazard must be monitored.
As a safety light curtain, the key selection parameters are detection capability, resolution, and protective height — none of which are detailed in this listing. The F3SJ series generally offers finger, hand, or body detection resolutions depending on the variant. Verify the protective height and range against your application's risk assessment before specifying. The bulk packaging indicates it ships as a single unit, not in a multi-pack.