The 45 mm width takes up a single 9 mm modular unit — five units wide — so it fits standard panel layouts. That zero forwards/backwards clearance means it can be mounted flush against a backplate or enclosure wall, saving depth in tight cabinets. The 97 mm depth is the body depth; account for wiring space in front of the spring-loaded terminals.
That is a high interrupting rating for a 45 mm wide device — it lets you place it close to a large transformer without needing upstream current-limiting fuses. The auxiliary contact ratings (1 A at 24 V, 0.5 A at 120 V, 0.5 A at 230 V) are for the integrated signal contact; they handle PLC or relay coil loads directly. The 0.1 kW at 230 V rating is the motor power the breaker can protect at that voltage — it is sized for small motors, not large drives. The maximum operating frequency of 15 switching operations per hour (AC-3) means it is intended for occasional motor starting, not continuous jogging or high-duty-cycle applications.