You have to twist the brush in one direction only because the head will unscrew. The under the rim brush does not reach the top of the bowl. Kind of disappointed. I have an old toilet, so maybe this was designed for newer ones.
What a great product the toilet scrub brush with rim cleaner along with all other OXO products. They are on the mountain top for this. No one comes close. OXO is THE BEST PERIOD!!!!.