The XS508B1PAM12 is an 8 mm shielded inductive proximity sensor from the Telemecanique XS5 series, with a 2 mm sensing range and PNP normally-open output. It runs on 12-24 VDC, sinks up to 200 mA, and terminates in a 4-pin M12 connector. The stainless steel 303 body with nickel plating and IP67 / NEMA 4X sealing make it a direct choice for washdown zones or corrosive atmospheres where plastic sensors won't hold up.
If you're cross-shopping against the plastic-body XS9E11RPBL01M12, the two are not mechanical or electrical drop-ins. The XS9 runs NC PNP at 100 mA max, senses 10 mm unshielded, and its plastic housing can't take the same chemical washdown as the 303 stainless body here. The XS508B1PAM12 is shielded for flush mounting and delivers a 2 mm range: that saves panel depth if the target is moving close in, but loses the longer standoff. Pick the stainless part when hygiene or corrosion resistance drives the BOM; pick the XS9 when you need normally-closed logic or a 10 mm window and plastic is acceptable.
M8 threaded body mounts into a bracket or tapped hole; 4-pin M12 mates to pigtail, wire as 3-wire PNP: brown +12-24V DC, blue, black output; shielded face allows flush mounting without derating 2 mm range; LED shows state during commissioning.