It's designed for line protection — the primary feeder or distribution circuit in a panel, not motor or generator protection. The ETU340 gives you adjustable thermal and magnetic settings, which is what you want when coordinating downstream breakers in a selective system.
This MCCB carries a 440 kA interrupting rating at 240 V AC and still holds 330 kA at 415 V and 440 V. At 690 V it's still good for 52.5 kA.
Panel fit and environment
Dimensions are 105 mm wide, 181 mm tall, 86 mm deep — that's a 4.13 by 7.13 by 3.39 inch footprint. Power dissipation is low at 0.5 W maximum, so heat buildup in a dense cabinet isn't a concern.