1. Shank: M14 thread, Chamfer angle: top angle 53 degrees, Chamfer diameter: 35mm, Total length: 45mm, Working depth: 35mm, Grit: #80. 2. This diamond countersink drill bit is a versatile diamond countersinking bit, designed to enlarge and shape existing holes for porcelain, ceramic, granite, tile, glass and marble. Also easily create round-shaped indentations to accommodate pipes or electrical wires. 3. High hardness and toughness. This granite diamond drill bit is made of quality diamond superior and durable metal. It uses these high quality raw materials to ensure more efficient cleaning and cutting. Very useful for improving the finish of the exposed hole edges. 4. Economical, a standard drill bit plus this versatile countersink bit, you are able to create many different hole sizes (0-50mm), without the need to purchase several different bits. 5. The diamond drill bit cannot be used to drill holes, but to enlarge and shape existing holes. It fits on the M14 thread angle grinder