The Siemens 3RH1140-1AN60 is a SIRIUS auxiliary contactor, Size S00, with 4 normally open (NO) instantaneous contacts. It's rated for 10 A at AC-12 duty, which covers the control-circuit switching you'd expect from an auxiliary block — relay coils, contactor coils, PLC digital inputs, that class of load.
The 10 A AC-12 rating is the key number for control-circuit duty — it's the maximum resistive current the contacts can make and break. For inductive loads like contactor coils, derate to the AC-15 values: 6 A at 230 V, 3 A at 400 V, 1 A at 690 V. The 4 NO configuration gives you four independent auxiliary circuits, which is enough to signal 'contactor on' back to a PLC, interlock a second starter, and still have a spare for a local pilot light. Wire termination accepts 2x 0.5-1.5 mm², 2x 0.75-2.5 mm², or 2x 4 mm² solid — that covers standard control wiring up to 12 AWG. The IP20 front protection is typical for inside a panel; no washdown rating here, so keep it behind the enclosure door. Shock resistance is 10g / 5 ms and 5g / 10 ms — fine for normal industrial vibration on a machine base or conveyor section.
The Size S00 footprint is 45 mm wide, 57.5 mm high, 72 mm deep. Zero side clearance required for adjacent devices, so you can butt it against the next S00 contactor or overload relay.