Creating a new list based on conditions

Hi, first time poster here. I have a predicament that gives me extra headache every month, so I was wondering if I couldn't work around it by using some smart solution, and I was hoping to find it here...

This is the situation:
I have a list of between 10 000 - 20 000 rows, with different part numbers that are classified, and I would like to populate a new list using the info in that list but only the ones classified with an "A" in one list, "B" in another and so on.

I want to be in cell A1, use this formula, and the first part number (which is the unique no that I then can do a Lookup with) with classification "A" should pop up. I can then fill the series until the list is complete.

Today I have to Autofilter, copy - paste every one, which is really tedious..

I have attached a simple example which shows what I mean...

Best regards and thanks in advance,

Dubbelito