The Omron EESX952W1M is a transmissive photomicrosensor from the EE-SX95 series — a slot-type sensor with a 5 mm gap, NPN output, and switchable Light-ON / Dark-ON logic. It sits in a 12 × 12 × 13.4 mm block with a 1 m cable, runs on 5 to 24 V, and switches up to 50 mA. The 500 µs response catches fast-moving objects on a conveyor or in a pick-and-place station — fast enough for most part-present and edge-detection jobs inside a machine.
The 5 mm slot means the flag or tab passing through must be under 5 mm thick — common for cam-actuated flags on rotary actuators or thin-edge detection on small parts. The NPN output sinks current to common, which is standard for most PLC inputs in the 24 VDC world; just make sure your input card is sourcing (PNP). The 5-24 V supply range means it runs on the same 24 V rail as your controls, or on a 5 V logic rail if that's what the board carries. IP50 means it's protected against dust ingress but not sealed against water — fine inside a control cabinet or a dry machine guard, but not for washdown zones or outdoors. The 1 m cable is pre-wired; if your panel layout needs more reach, you'll splice or extend it at the terminal block.