Review on CBKIT1 Monster Diamond Concrete Tool by Toolocity by Jay Matlock

Works great. There is a little learning curve. You should start at about a 45 degree angle so you only drill about 1/4 of the bit. Then slowly bring the drill to a vertical position and it will stay where you want it. I've drilled through 5/16" porcelain tile with the largest bit. This took me 3 to 5 minutes. I stopped every 15-20 seconds to squirt water onto the surface.