The Siemens 3RF3320-1AA02 is a 1-pole solid-state contactor from the SIRIUS 3RF33 family, rated for 20 A in AC-1 duty at 40 °C. The control circuit accepts a wide range: 24-230 V AC or 24 V DC, which simplifies stocking a single part for panels with mixed control voltages. Termination is via screw terminals, the standard for panel builders who prefer a positive mechanical clamp over spring-cage.
The 27 mm width means it occupies one slot in a typical enclosure layout — plan your fill factor accordingly. No auxiliary contact block is integrated; if you need status feedback, you'll add a separate monitoring relay or a contactor with an integrated auxiliary.