Making countifs reference inequalities

I have a countifs formula built that is not working.

=countifs(Sheet1!A:A,$B$1,Sheet1!B:B,$A6,Sheet1!U:U,<5)

The problem comes because I want the countifs to pull all cells less than 5 in column U:U that meet the other criteria. I keep getting an error message and can't figure out how to write this equation. I have tried naming other cells in the worksheet 5, 10, etc and referencing them but it still does not work. The second problem I would have moving forward is for the formula to pull all cells less than 10 but greater than 5.

Thanks in advance for the awesome help!!