Dry Diamond Core Drill Bits 1-3/8 Inch (35mm) Tile Hole Saws for Porcelain Ceramic Tile Marble Brick Hole Saw with 5/8-11 Thread Plus 3/8 Inch Hex Shank Adapter

I bought this diamond bit to drill a couple of holes in a quartz counter top. This bit did the job with ease!I'm not sure of longevity but it seems like it would hold for many more holes. For the price, it can't be beat.

Drilled holes well I was using a variable speed grinder can use with water to keep the dust down so far I’ve drilled about 10 holes and it’s cutting good

I had a idea for something and couldn’t have done it without this product

This drove through my quartz countertop with ease .. no problem at all. I was impressed, to say the least. After I started the hole (drilled in a couple MM) I created a dam (with plumbers putty) around the spot and filled it with water … this kept the dust away and actively helped cool the drill bit too. Save some $$ and DIY with this workhorse bit.

We cut into stucco and brick for electrical install in a remodel of several buildings. We keep buying these only because we feel they are adequate at doing what we need them to do. Very happy with product

Did a good job drilling facet holes through Granite and Quartz.

Used twice to drill holes in granite 1.25" thick. Slow going but it worked. Be sure to use plenty of water and low speed. My problem was that the mandrel bent on the second use. Therefore cannot recommend.

Installer wanted $75 per hole to drill into my countertop. Bought this drill bit for a fraction of the cost instead. Watched online videos for proper RPM and technique. The only unknown is the longevity since I only used once, but overall, very pleased with the results at a fraction of the cost.