The Siemens 3RG4111-7AG33 is an M8 inductive proximity switch with a 2 mm flush sensing range, PNP output, and a plug connector. It's a standard DC three-wire sensor for detecting ferrous targets in tight spaces — conveyor diverter gates, pallet stops, or end-of-travel on a linear slide.
The 2 mm flush sensing range means the sensor face can be mounted level with the surrounding metal without false triggering — useful on a machine frame or bracket where the sensor can't protrude. PNP output (sourcing) is common for PLC inputs that expect a positive signal; the plug connector simplifies replacement without rewiring the cable.