The headline number here is the 100 kA short-circuit breaking capacity at 400 V (and also at 240 V and 500 V), which tells you this breaker can safely interrupt a fault up to that level without the arc flashing over or the device rupturing. That SCCR is what lets you coordinate it with upstream protection and avoid cascading failures. At 690 V the interrupting capacity drops to 4 kA — still useful for most 690 V motor circuits, but you need to check the available fault current at that voltage. The 45 mm width (three module spaces on a DIN rail) and 97 mm depth mean it fits standard 35 mm DIN rail enclosures with the screw and snap-on mounting per DIN EN 60715. Spring-loaded terminals on the main current circuit accept 2x 0.5 to 4 mm² solid or stranded — no ring lugs needed, which speeds up panel wiring.
Mounting position is any — vertical, horizontal, flat — so you are not constrained by orientation in a crowded enclosure. The 106 mm height and 45 mm width let you pack several of these side by side on a DIN rail. The screw and snap-on fastening means you can clip it onto the rail without tools, then secure with a screw if vibration is a concern. Operating temperature range is -20 to +60 °C, storage -50 to +80 °C, so it handles typical industrial panel conditions without derating concerns in most environments.