The Telemecanique XUB2BKSNM12T is the emitter half of an 18 mm tubular through-beam photoelectric sensor from the XUB series. It sends a continuous infrared beam across a 15 m gap to a separate receiver — when something breaks that beam, the receiver switches its output. That 15 m range covers conveyor belts, warehouse aisles, and automated guided vehicle paths where you need detection across an aisle or through a pallet opening. The 1 ms response time means it catches fast-moving parts on a packaging line without missing a beat. It runs on 12 to 24 VDC and connects through a standard M12 4-pin male connector — the same footprint you see on most modern proximity and photoelectric sensors, so it drops into existing M12 cabling without re-terminating. Three wires: brown for +VDC, blue for common, and the black wire is unused on the emitter (the receiver carries the output).
Where you'd use it — the enclosure story
The nickel-plated brass barrel and PMMA lens are sealed to IP67 and NEMA 4X/12. That means it's dust-tight, protected against temporary submersion, and rated for corrosive environments (the 4X part). Think washdown zones in food processing, outdoor conveyor gantries in a lumber mill, or a chemical dosing skid where splashes are routine. The 18 mm threaded barrel mounts through a standard 18 mm knockout or bracket — same hole pattern as a limit switch or an inductive prox. If you're retrofitting an older through-beam pair, the M12 connector saves you pulling new cable; just swap the pigtail.