When any object (typically a hand or body part) breaks the beams, the curtain triggers a stop signal to the guarded machine's safety circuit. This is the core component for point-of-operation guarding on presses, assembly stations, and robotic cells where personnel access the hazard zone.
The F3SJ-B1265P25-02TS belongs to the F3SJ series, Omron's compact safety light curtain line. The series designation tells you it uses a 25 mm beam pitch, which gives finger-detection capability (14 mm resolution) — suitable for applications where operators reach into the guarded area. The bulk packaging means the unit ships as a single assembly, not in a multi-pack or reel. No special handling required beyond standard ESD precautions for the controller electronics.