It integrates a B40 A overcurrent trip with a 10 mA residual-current sensing element in a single 1+N-pole unit, rated for 6 kA short-circuit breaking capacity. The D=70 mm dimension refers to the depth of the device, which fits standard Siemens distribution boards and consumer units.
The 10 mA residual-current sensitivity (IΔn) makes this unit suitable for circuits requiring enhanced protection against electric shock — typically final circuits supplying socket outlets in wet areas or equipment with higher leakage risk. The B40 A characteristic provides magnetic trip between 3× and 5× rated current (120–200 A), suited for resistive and moderate inductive loads like lighting, small heaters, or control transformers.