Has worked for anything I've ever needed it for. A few went missing but that's my fault.
Are these stamped in the metal? Yes. They have a machine mark stamped into each socket as well as lighter contrasting labeling painted on them for easier identification. 1) In what country are these made, and (2) are the socket sizes stamped into metal as well as laser printed? I don't know the country of origin. The sizes are not stamped into the metal. But I think these are great sockets and they come in really nice cases. I put a full set in each of my work trucks and use them regularly. does this product have a warranty Yes. The manufacturer's warranty applies.