Review on Diamond Granite Drill Masonry Tools: Unmatched Precision and Durability by Centerfold Montague

Worked great. I installed a water filtration system and had to make a 1/2" hole for the faucet. I was a bit nervous at first, but everything went pretty smoothly. Method I used: I used plasticine (whatever I had), to make a ring where I wanted to cut to hold some water. Pour some water into the putty ring. I started at an angle to cut the groove and then smooth it. In order not to burn the bit, trimmed I for about 20 seconds, stopped to let the bit cool for 10 seconds, wiped away the dirty water with a paper towel and added fresh cold water.As I drilled, I rocked the bit clockwise and didn't put much effort on it .I took my time and made it through the countertop in 5-10 minutes.I would buy it again but I probably wouldn't have to as I have 4 bits and the one I used wasn't boring at all.