Drill glass, marble, masonry, rocks, concrete- just about anything you want!
Super duty diamond coating on nickel plated high speed steel will give you excellent results even in semi-precious stones.
Fluteless design brings more diamonds in contact with your stock. Lasts longer and works better than twist designs.
Sizes: 1/8", 5/32", 3/16", and 1/4"
Note: use on a low speed with coolant (water/oil)