speakers, How are they measured?

[Mark One]

I've got a polo 6N runaround and I'm thinking of some cheap JBLs for it.

How do you measure the speakers? I don't know if these are 16 or 17cm

 

[Sheilas’ Wheels]

The cone itself, across.

Not the metal rim.

 

[MT AUDIO]

cone edge to cone edge,but it wont matter if you have 16cm or 17cm,you can make both fit

 

[Mark One]

cheers