1.how to use:To maintain stability and accuracy, use a desktop press to place a piece of wood in a container filled with water, place the housing on the wood, cover the housing with water, and use slow drilling speed and gentle pressure to allow the burr to complete the work. Water is needed to lubricate and keep the drill bit cool to extend its service life.
2.around 180 to 220 grit
3.Head Diameter:1.5mm; The positive tolerance of the head diameter of the grinding bit is 0.1-0.2mm
4.Shank Diameter:2.35mm(3/32"); Suitable for tool with 3/32 inch or adjustable chuck
Note: The color of the item may vary slightly due to photography and your own computer
Feature:
This diamond coated core drill bit removes a complete circle from glass, tile, marble, granite, ceramic or other materials and only needs water for lubrication.
Excellent for making clean and accurate hole on glass, tile and marble.
High quality and long life span.
Start your hole diagonally, make a round trace and then hold drill straight.
Add water for coolant and drill slowly.

Warm reminder: Drill bit Replacement for Generally need to be drill slowly on the stone when start to drill, wait for the stone to open hole and then drill hard. Like hard stones, or ice types, miscellaneous stone, agate, etc., the punch may not be durable. If it is used on hard stone, it is recommended to add emulsified oil to lubricate the Drill bit.

Specification:
Material:Metal,Diamond
Color:Silver
Shank Diameter: 2.3MM
Head Diameter: 1.5mm
Sand length: 6-8MM
Full length: 42mm
Dimension:2.3 x 42mm/0.09 x 1.65"(Dia x L)
Weight:25g

Package Include:
20 x Diamond Coated Hole Drills