That dual rating is the key spec to check against your panel's upstream SCCR — if the fault current at the breaker's location exceeds 10 kA, you rely on the 60947-2 figure, provided the installation is designed to that standard. The breaker occupies 4 modular width units (4 MW) on a DIN rail, so it fills 72 mm of rail space.
For a buyer holding a BOM line with this order code, the fit is straightforward: 20 A C-curve, 4-pole, 10/20 kA breaking capacity. Confirm the upstream SCCR at the breaker's location — if it's above 10 kA but within 20 kA, the IEC 60947-2 rating covers you.
Deployment context
The 76 mm depth and 90 mm height leave room for gland plates and cable bends in a typical 200 mm deep enclosure. The quick-assembly fastening method means it clips on without tools and can be removed with a screwdriver push on the clip — useful for panel builders who need to swap units during commissioning. The design is specified for railway applications and mechanical engineering / industry, which means it has been tested to the vibration and temperature ranges those environments demand — the -40 °C to +75 °C operating range covers unheated enclosures and hot cabinet interiors near transformers or drives.