The Siemens 3RF3365-3BA24 is a 1-pole solid-state contactor from the SIRIUS 3RF33 series, rated for 27.5 A in AC-15 duty at 40 °C ambient. That AC-15 rating means it's designed for switching electromagnetic loads — solenoids, contactor coils, and similar inductive devices — not resistive heaters or motors. The load circuit spans 48-460 V AC, and the coil takes 110-230 V AC for instantaneous switching. Termination is via ring cable terminals, which give a secure, vibration-resistant connection in a panel. This is a solid-state contactor, so there are no moving contacts to arc or wear out from repetitive switching.
The ring cable terminals accept lugged wires, which is common in North American panel practice for higher-current solid-state devices. At 105 x 50 x 125 mm, it takes up about the space of a small contactor — plan for clearance around the heat sink if you're stacking multiple units side by side, as solid-state contactors dissipate heat even when closed.