Bigclive did a teardown of a failed Rolec MCBO. It looks like the one aboveDo be aware that Rolec's reputation for choice of RCBO is poor. We've already seen a couple of their choices fail.
Lots of the blue-text B40 ones have failed. A couple of the green-text C40s have overheated on the right hand side.
I see yours is labelled "D40" - maybe they're changed yet again? Please do keep an eye on this, maybe take the front cover off after a few weeks & look to see if any sign of overheating. It only costs about £25 to get one that's deffo from a reputable mfr like Garo. May even be worth getting a Garo in as a standby, on the just-in-case principle.
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