It's a quarter turn valve. I found the exact faucet stem I purchased and it's identical to the old one. If you go to F.D. & Sons Hardware and search for STOCK #: 17312B you can see what I'm dealing with. The brand is Danco. Let me know what you think I need to do further to fix the leak since replacing the old one didn't work. Thank you

Tell us exactly where it's leaking from. Out the spout? From the stem? Where? Tom