How a cryptographer uses a key engraver

Legendary cryptographer and security researcher Matt Blaze (previously) somehow acquired a key engraver and now he's 'using it to engrave entirely serious labels on my keys that are not in any way ironic or confusing.'

I just got a key engraving machine. Because I am a very responsible adult I’m using it to engrave entirely serious labels on my keys that are not in any way ironic or confusing. pic.twitter.com/M2BIAet8sC— matt blaze (@mattblaze) February 13, 2019