Siemens 3RG40 11-3AA00 is an inductive proximity sensor in a cylindrical M8 stainless steel housing. It detects ferrous targets at 1 mm, switches PNP normally closed, and runs on 10-65 V DC. The M12 connector keeps field wiring quick — no gland work on the sensor body.
1 mm sensing range means it detects a target only when the face is practically touching — use for micro-position detection, not pass-through sensing. PNP normally closed output means the load is energized when no target is present; the output switches off when metal enters the field. 10-65 V DC supply covers most 24 V control circuits with headroom for longer cable runs.