French Drop tanks

A simple question here.
Why are french drop tanks a different shape to all other countries drop tanks?
Rafale with tanks

Mirage 2000 with tanks

They seem to be over sized at the front and not very pointy when compared with other air forces drop tanks.

F16 tanks

Tornado GR4 drop tanks

One final picture with a big variety of aircraft. Again the french tanks look a lot less aerodynamic compared to all other tanks.

Are all NATO aircraft equipped with the same size of tanks? Do they have options on what to fly with? Does the RAF always stick with the same size/shape of tank for all aircraft?

One last question in the quiz, What’s the biggest drop tank used on any aircraft?