It combines a 40 A C-characteristic MCB with a 30 mA Type A RCD in a single DIN-rail module, rated at 4.5 kA breaking capacity on 230 V AC. The C-curve means it's sized for motor and lighting circuits with moderate inrush — the magnetic trip holds through starting surges up to 5–10× rated current, then clears a hard fault before the cable gets hot.
The 1P+N format takes a single module width, so it's a direct fit for compact consumer units or sub-distribution panels where space is tight. Type A RCD detects both sinusoidal AC fault currents and pulsating DC fault currents — that's the right choice for circuits feeding electronics, VFDs, or washing machines where a plain AC type would miss half the fault signature.