FASTORS Dry Diamond Drill Bit Set,10-Pack Diamond Core Drill Bits for Tile Ceramic Marble Granite Glass Brick Stone,1/4 Hex Shank Size 6,8,10,12 mm

I used this to drill a hole in our quartz countertop for an extra faucet (we got a reverse osmosis water filtration system, which I also highly recommend.)I tried it at first without a jig and it was clear that was a bad idea so I used my portable drill guide. I was concerned about not being able to clamp the guide down but it wasn’t necessary. Just using that to keep it straight made it so that the hole was perfect.I used two bits to get all the way through the stone. It’s possible I could have done it with one but so much dust built up on the bit after about 2/3 of the thickness that I decided to switch. I also then added water. I’m not sure if that helped with cutting but it was getting EXTREMELY hot and was starting to smoke and it helped with that.The guide was one that’s listed on ace hardware for $43 but I’m certain I got it for less at harbor freight. You’ll definitely need one if you’re going through stone, especially if you want to preserve the finish of the stone, as it’ll jump around a ton.I did not use a hammer driver, as I wasn’t sure how that would go, so I just used my lil’ old battery powered Ryobi drill. I’d say it took about 2 min to get through 1.25” of quartz.

The product came quickly and I was able to get the job done.

Solid bits that do walk a little if you don't get them on edge of have a bearing tool to align them. Overall they work and are a good price. It's also nice that they can be put in an impact if you need to.

Worked great for making drain holes in ceramic bowls to turn them into planters.

I have only used 2 of the 6mm I had to use Tapcon bits to start the hole as these walk all over the tile trying to get started, it took one and a half bits to mount 2 safety hand rails in my mothers shower. They did make a clean hole for the anchors once started.