12 Pcs Diamond Drill Bits for Ceramic, Diamond Hole Saw Drill Bit Set Kit, Premium Glass Drill Bit for Bottles, Pots, Marble, Granite Stone, Tile Cutting 0.16 Inch - 1.18 Inch（4 mm - 30 mm） YLYL

I got the 12 piece set thinking I’d go through a few of them just to get what I wanted done. To my surprise, I drilled through 7 planters and the one drill bit I used seems like it could endure some more work! It takes a bit getting used to (you can see the learning curve in the picture) but once you get the hang of it it’s easy. I started drilling gently at a 45 degree angle to first create the initial dent that will allow the drill bit to stop sliding - tape also helps provide a good initial grip. I then added water as I drilled. Remember to wear eye protection in case small sharp pieces fly out (I just used my big thick sunglasses). Lastly, it does get a bit messy, I did the work outdoors while wearing clothes I don’t care for. Happy to now have proper drainage in planters I love

I have lost a few pots and plants due to holding too much water for lack of drainage holes. I was a little nervous to drill, but they worked! At first I tried to drill straight down, but my husband tipped me off to angle the bit and do one edge first to bite in, then bring upright. Worked great!I did get a couple chips on the edges, but it's the bottom of the pot, and no cracks, so no big deal. Probably user error than the bit. I did 6 holes with one bit, could probably drill a few more, so I'd say that they are fairly durable. The pack is a good value for number of bits.

Well now that I've used them they are good enough for the price. I've had a set for a month, and I've tore three of my main use ones up 18, 20, 22. Main problem is they don't cool good and they can't handle real torque. So if I'm drilling Jasper or agate it's slow and careful.The ones that broke18 mm eventually wore out20 mm melted22 mm the weld twisted offMind you I am using a 1968 sterling 12 speed drill press with a counter weight set drilling and water cooled. So it is definitely probably too big for these bits.Going to go oil cooled and see what it does, I know my saws like oil.

Works very well, also the different assortment of sizes is very convenient

Bought these to drill holes in flowers pots, they work great!! You just have to be slow and know what you are doing. I have drilled both glass and ceramic no problem. Make a few coffee mugs into pots

Didn’t work well for me. I was trying to drill porcelain and it could barely get through.

These work great! I have not broken a pot since I got them. I run cold water then this. Doing this every 10 seconds or so. Clean cuts too.

Used these on my ceramic planters and the worked out great. There was a variety of sizes which is very handy. made out of good quality material for what I needed it for.