The Square D XCKJ10513D is a heavy-duty, non-plug-in limit switch from the Osiswitch family, built for position sensing in wet, dusty, or washdown environments. Its SPDT snap-action contact is rated 240 VAC 10 A and 250 VDC 0.27 A — the AC figure covers most motor-starter and solenoid loads, while the DC rating is low enough that you'll want to verify it handles your inductive DC circuit without welding. The rotary head with steel roller lever gives a 23° pretravel and 90° total travel, with 11° differential; the 33.3 oz-in operating force means it won't trip from vibration but will catch a machine cycle reliably. Enclosure is NEMA 1/2/4/12 and IP66, so it's suitable for indoor and outdoor use where hose-down or high-pressure spray is routine — think food processing, car washes, or aggregate plants. Body is Zamak zinc alloy, which resists corrosion better than painted steel in those settings. Connection is via an M12 5-pin male connector, which simplifies field wiring and replacement: unplug the old head, plug in the new one, no re-termination.
The 240 VAC 10 A contact rating is the headline number, but the 250 VDC 0.27 A rating is the one that trips people up. If you're switching a DC solenoid or a small DC motor, that 0.27 A limit is the hard ceiling — DC arcs are harder to extinguish than AC, so don't assume the AC rating scales down. The SPDT configuration gives you both N.O. and N.C. contacts in one housing, which is useful for dual-channel safety circuits or for signaling a PLC while also dropping out a contactor. Operating temperature range is -13 to 158 °F (-25 to 70 °C), so it's fine for unheated outdoor enclosures in most climates. The IP66 and NEMA 4/12 ratings mean it's dust-tight and protected against hose-directed water — that's a step above NEMA 1/2, which only guards against falling dirt and dripping water. If your application sees direct spray from a pressure washer, this switch will hold up.