Hi,
The adapter is rated at 10amps and is SABS approved. The L&N pins are hollow, being made from brass tube. Crabtree are a big concern in South Africa these days judging by their website & product ranges. Not sure how big they are in the UK though. The construction of the adapter looks a bit 'plasticky' to me as well but the Euro two pin plug is a good firm fit.
I had to smile at the idea of a Brit (me) buying a South African fitting from a Dutch couple in France. Cosmopolitan, or what?
Cheers, Pete