What it is
The ABB 1SAZ321201R1003 is a solid state overload relay sitting in the circuit breakers, fuses & protection / relays / solid state overload relays line, classed for motor-protection duty alongside thermal overload devices.
Where it sits in the panel
Solid state overload relays of this class mount under the matching ABB contactor frame and feed the contactor coil through the NC trip contact — the integrator's job is verifying the current range, trip class, and coil interface on the matching contactor before energizing, none of which the spec line here carries.