The Siemens 3RH1344-2DB40-0KA0-ZX95 is a SIRIUS auxiliary contactor in size S00, carrying 4 normally-open instantaneous contacts and a 24 VDC coil. The coil draws 3.2 W closing and holding, so the DC supply needs to deliver that continuously; the built-in varistor suppresses the inductive kick on de-energisation.
Rated insulation voltage is 6 kV surge withstand, which puts it in the IEC 60947-1 overvoltage category III range — suitable for fixed-installation panels without additional surge protection upstream. The thermal current rating at 24 V is 10 A; at 230 V it derates to 6 A, at 400 V to 3 A, and at 690 V to 1 A. Contact reliability is specified as one incorrect switching operation per 100 million at 17 V, 1 mA, which is the low-energy end — gold-flashed contacts would be better for PLC-level dry circuits, but this part is rated for the typical 24 VDC auxiliary load.