They are submarines of the same type, basically the same submarines

3rd of Type B1 submarine I-19

7th of Type B1 submarine I-26

Of course the same

I-168

Let's talk about ship width...

Hey!

Widest, 12 m

I-401

This must be mistaken...

So you are a hidden busty girl!

Hold it! Stop using bust to represent ship width!

Let's talk about displacement...

I-168

Ro-500

I told you not to use bust to represent displacement!!

Traitor...

I-58

I-8

I'm finally among the busties!