These have a strong lead that didn't break when I used it, like most "adult" mechanical pencils (so annoyingly) do

The lead in them is thick so it doesn't break as easily

You can retract the lead when you aren't using.

there’s not enough lead in each one

There is enough lead in the to last quiet a while - we use them daily to practice writing or just to doodle - which you will see in the video below.

I like the big leads that don't break under pressure.

We love 1.3 lead