The 6 kA breaking capacity per EN 60898 (5 kA per UL 1077 / CSA C22.2 No. 235) tells you it can safely interrupt a fault up to that level without welding its contacts or cascading upstream. Per the datasheet, the rated current derates with ambient temperature: 3.76 A at 40 °C, 3.5 A at 50 °C, and 3.37 A at 55 °C — so if the panel runs warm, the actual load limit drops.
Its width is 54 mm (3 modular units), depth 76 mm, and installation depth 70 mm. Mounting position is any orientation. Sealable, halogen-free, silicon-free construction suits environments where outgassing or contamination matters.