What you're pulling off the shelf
The 1SAZ311401R1002: For a panel wireman, the relevant question is straightforward: does it drop on the rail next to the contactor it was designed to protect, and does the wiring channel leave room to land the CT leads cleanly. As a solid state unit in this class, it handles the motor protection loop electronically rather than through bimetallic strips, which is the reason it shows up in this category alongside thermal and electronic overload siblings.