Rated operational voltage is 400...415 V AC at 50 Hz, with a breaking and making capacity of 500 A per EN/IEC 61008-1.
Clip-on mounting onto a DIN rail — standard 35 mm symmetrical rail. Takes up 8 x 9 mm pitches (72 mm wide), 81 mm tall, 75 mm deep. Neutral is on the left (4P configuration). Tunnel-type terminals accept 1...35 mm² rigid or 1...25 mm² flexible copper; strip 14 mm, torque to 3.5 N.m. That's a solid lug range for 40 A — you can land a 10 mm² feed and still have room for a 16 mm² downstream if the run is long. IP20 finger-safe front, but once it's in the enclosure the panel door handles the real protection.
The 100 mA sensitivity is worth a second look. That's not a 30 mA personal-protection trip — it's set higher to avoid nuisance tripping on equipment with natural leakage (heaters, drives with input filters, long cable runs). Type AC means it catches sinusoidal AC fault current only; if your load includes VFDs, UPSs, or switched-mode supplies that generate pulsed DC fault currents, you'd need a Type A or Type B RCCB instead. The 4000-cycle mechanical and electrical durability is standard for a switch-disconnect in this class — it's not a daily-operate contactor, it's a protective device that should sit closed unless something goes wrong.