Sorry for the long post, you can look at the bold text near the end directly if you aren't interested with the historic.
When buying voltage some Voltage-Level Translator online, they sent it with round machine pin, I didn't used them, because I like the square pin better, they are less fragile.
Then I was searching for breakable female headers, because I didn't like the way standard female headers looked after I cut them and to loose a pin each time. Not knowing what keyword to use I couldn't find anything.
I went to local store and ask if it exist and they sold me machine pin breakable female headers, they are really low rise. But square pin don't fit in. You could use machine pin, solid wire or dip IC.
I went back to the store and ask for machine pin male header like I received with the Voltage-Level Translator, they told me it don't exist and after some arguing and showing them picture. He said that machine pin deform a little and aren't supposed to be used a socket. He said he would search and call me back.
The low profile breakable female headers he found is so amazing that I had to share with all of you!
He also sold me standard male headers but I realized afterward that the pin are too long and stick out a little. But looking on digikey for Samtec low profile socket strips, they reference mating product!
Yes they come at high price!
Watch out for component height like RJ45 connector, USB B socket, barrel jack, dip socket with chip.
But it can be used easily on Arduino Leonardo without headers without soldering the barrel jack and Adafruit Arduino Metro but you'll need to unsolder the barrel jack.
If someone find some stackable one with long leg, let us know!
I hope it will help a lot of people!