Went through 4 ceramic teacups and the drill bit broke and broke on the 5th cup. I had plans to drill drainage holes in many of my pots. I will return and buy from a specialty store that specializes in contractor tools. *** Ignore the initial review below if you can't use this kit quickly and once. they don't last. I managed to drink 2 cups of coffee and 4 cups of tea. That's all. *** Great for what I bought the set for. The aim is to drill drainage holes in ceramic plant pots. I will update the review after using the drill kit for drilling drainage holes in some of the stone pots, glass pots and other pots I currently have. I practiced on ceramic coffee/tea mugs. Here's what I've done with success: 1. Use water as instructed2. I put a rag in the sink under the mug to reduce vibration and sliding so the mug doesn't break and I cut myself3. I used the largest piece of 12mm.4. I walked slowly and stopped often to see what I was doing and to be careful as I had never done this before. As a result, there were 2 clean holes in the middle of both cups. See attached photos. I did it in the sink. But I would probably do it outside by pushing the hose forward on larger pots.