Three poles, IP40 on the front face — that's splash-resistant from the panel door side, but the bus connections are exposed inside the enclosure.
Breaking capacity is where this breaker earns its panel position. At 415 V and 440 V it still holds 75.6 kA; at 500 V it drops to 52.5 kA; at 690 V it's 3 kA, so if your system runs 690 V you need to check coordination carefully.
The 105 mm width is three pole spaces at roughly 35 mm per pole, so it occupies the same cutout as other 3-pole MCCBs in the SENTRON family.
For a BOM line or a line-down replacement, the key fit confirmation is the 100 A continuous rating with no temperature derating up to 70 °C, the 3-pole configuration, and the ETU320 trip unit.