Fyi. I recently found that our bathroom bowl sink had a slight leak around the drain. I noticed a little water drip under the sink after a camping trip where we had to leave the water dripping due to the freezing temperatures. After close inspection, I found that there was a slow leak at the drain where it seals around the sink bowl. Once I disassembled it, I found that the rubber gasket between the sink bowl and drain was leaking. I took everything apart and found the countertop material was wet. I dried it out and reassembled it using plumbers putty in addition to the gasket as well as Teflon tape on the drain pipe threaded joints just to be sure. It could have destroyed the countertop over time but we were lucky. Keep an eye on your plumbing. It appears the factory does not use any sealer other than the gaskets. The countertop substrate is a sponge to any leaking water that may come in contact with it. Our unit is over 1 1/2 years old and we still LOVE it.