Highlighting all duplicate rows without removing it

Hi I have my data listed in numeric order in column B. These are part numbers or skus from my supplier.

Example:
B25: 10081
B26: 10082
B27: 10082
B28: 10083
B29: 10084

As you can see the data in B26 & B27 are duplicated. I need to make a modification to one of the part#'s of 10082 to make it unique.
What you don't see is the desacription is what's unique. B26 is size small and B27 is medium. I will manually make it 10082-S & 10082-M to make them unique.

I have a lot of data in this column so I would like to highlight the ones that are duplicated but I do not want to remove them. I know Excel has a feature in where you can go to Data ==> Remove Duplicates. I do not want to remove these, I plan on modifying the duplicate part numbers but I want to only work on the skus that are listed more than one in this column.

How do I isolate this data?

Thanks - YR

Perfect!! - Thank you