Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. It only takes a minute to sign up.
Sign up to join this community
I purchased this faucet and it seems like an easy enough installation. The bottom of this new faucet looks like this: 
Seems like all I have to do is screw something in and it will attach the faucet to my counter top.
My old faucet: 
Doesn't seem like it has the same mechanics. This is what I see under my kitchen counter top: 
How do I get that off? I've tried twisting it as if the shaft is threaded but I don't think it was loosening at all.
The black collar seen on the bottom picture is what is keeping the faucet on. It is a plastic nut that screws on the threads you see to clamp the faucet onto the countertop.
That is what you need to unscrew with the basin wrench (or any other that can reach).
That thing is so hard to twist off, you'll likely need a basin wrench, which is also sometimes known as a sink wrench. When I took my faucet off recently, I followed this article for the most part. The hardest part for sure was getting that unscrewed, but luckily I found a basin wrench and it went smoother.
