[Elecraft] OT: drillbit question

[Henning V. Mikkelsen]

Hi all
I know this is Somewhat off topic but I hope you can help me anyway.
I saw something on TV yesterday. In a program Ocean county choppers
they were using a kind of stepped size drill bit. Can anyone help on info
on this tool as I have newer seen anything like that before.  I must admit
I'm
a bit of a tool buff. And that one is definitely different.

73-
Henning