Issue Number has a letter in after link

After importing my comics, I select the series for the group of comics, then when I try to link issues, I get letters auto added to the issue number in my collection.

What is the letter after the issue number for?
Shouldn’t it just be the issue number by itself?

Issue column will show:
Issue number + Variant letter.

If you only want a number, you can modify your column to be the “Issue Nr.” instead of Issue.

Note:
I would worry though about having that number in the “series” field. That looks very wrong?

Is there a field to map the “Comic Code (or Series ID Number) to?
What field would you advise that data be mapped to?

For example:
That five-digit number is the Comic Code (or Series ID Number), often part of the indicia and circulation system, used primarily for tracking, distribution, and mail subscriptions during the 1970s. It uniquely identified the specific title and volume within Marvel’s publishing lineup, such as 02457 for The Amazing Spider-Man

The letter indicates the Variant.
For example A = Direction Edition, B = Newsstand Edition, etc…
For modern comics A = Regular edition, B, C, D, E are cover variants.

We don’t use that “Comic Code”.
You should import the Series name into the Series field, not that code.