The Siemens 3RG7401-0AB00 is a SIMATIC PXO320 K21 retro reflective sensor with a built-in polarisation filter — that filter is what lets it see through shiny targets without false triggers. It runs on DC 10-30V, outputs PNP light-on at 150 mA, and reaches 3 m range. The 2 m PUR cable (3x0.14 mm²) and IP68 rating mean it can live in washdown zones or wet plant floors without a secondary enclosure.
The polarisation filter is the key differentiator here — it rejects reflections from glossy or metallic objects that would fool a standard retro reflective sensor. That 3 m range is the rated distance with the supplied reflector; expect a shorter gap if you're using a smaller or dirty reflector. The PNP output is light-on only, so it pulls high when it sees the beam return. At 150 mA it can drive a small relay or PLC input directly, but don't plan on powering a contactor coil without an interposing relay. IP68 means it's submersible, not just splash-proof — good for food-processing washdowns or outdoor installations that see standing water.