[ihc] Flaring tool?

[Joel M Brodsky <jmbrodsky@xxxxxxxxxxxx>]

I have two flaring tools.  Use them often.
I'm curious about what it means to 'double flare' something.
Does that mean that there is a layer of material folded over the first one
so that the flared section is actually
a sandwich of two layers of material?
OR
Is a double flare just like a bulge in the line, like a flare-out followed
closely by a flare-in - like on a factory fuel pump outlet pipe for
mechanical fuel pumps on '70s SVs?

Thanks for clearing that up,

JoelB