I was a bit concerned that I didn't see any real cobalt stamping on the drills, nor any stamping, only etching. They look pretty well made. I've tried Bosch and a couple of Century Tool Cobalt's, some of which were great because they had 8% Co instead of 5%, but they claim to be a real deal and so far they drill just as well as they do. Any brand new drill goes through the aluminum I've drilled, so time will tell. Assuming they are real M42s, I'd say it's a lot.