During a visit to Home Depot for other purposes, I spotted a BrassCraft Zip-It. Seeing that I had a slow bathroom sink, I was willing to give the product a test, especially since it only cost $2.50.
First, I filled the sink with 3 cups of water, measuring carefully with that precise, scientific instrument otherwise known as a Legoland cup.
Three Legoland cups of water yields about this much water.
Next, I measured how long it took for all the water to drain from the sink. A disappointing 24 seconds, per iPhone.
I could insert the Zip-It really easily down the drain, but pulling it back up took some wiggling. I think all the notches were catching onto parts of the drain. The Zip-It didn’t pull up a hairball or any large masses, but it did pull up a lot of black gunk.
After wiping away all the black gunk and rinsing the sink clean, I refilled the sink with 3 cups of water. The time to drain was a much-improved 9 seconds.