The hole diameter of the drill bit is 4mm, which is about 1/4 inch.it's 2 inches long and it could be fit into a standard bit extension.It can cut tidy, smooth, no broken edges and no tremor phenomenon
.If you're drilling into stone, make sure you use water and don't push too hard. to make a shallow surface etching such as hieroglyphs on a sandstone cave wall with a cordless drill or if using on soft rock they could be successfully used to engrave rock
Note: Please pay attention to add water to cool when processing , overheating will increase the loss of powder
able to get perhaps a total drilling of 5 or 10 holes in ceramic floor tile with a single bit if drill wet and don't hurry. Softer wall tile allows more holes
Small incision resistance, improved the openning speed
Note: The color of the item may vary slightly due to photography and your own computer Hole Saw for Glass It can cut tidy, smooth, no broken edges and no tremor phenomenon Small incision resistance, improved the openning speed Excellent for making clean and accurate holes on glass and tile Designed with diamond coated tip and sturdy metal body, gives good performance and longer life Specifications: Product Name:Glass Hole Saw; Material:Metal Color : Silver Cutting Hole Outer Diameter: 4mm/0.16" Shank Hole Diameter:2mm/0.07" Shank Dia (Approx.):2mm/0.07"; Total Length : 50mm/2" Size:5x0.2x0.2cm/2x0.07x0.07Inch Weight:25g