Correct size for snap fasteners (poppers)

[IconBycon]

 

I’m adding an extra snap fastener to a leather jacket, but I’m stuck on sizing when ordering online.

I measured the visible stud at a little over 7 mm (see photo).

What industry standard size name should I be searching for?

Also, when sellers list sizes, what does it refer to (post length, socket size, etc.)?

Any guidance (with links please) on what to buy so it matches the existing snaps would be appreciated.

 

Edited 1 hour ago by IconBycon