Features: The drill bit is chrome-plated and hardened to improve performance, strength and durability. 3 pieces of diamond grinding bits in 3 sizes, namely, 1 inch, 3/4 inch, 1/4 inch, along with 3 matching allen wrenches, different sizes and complete combination to fully meet your DIY use. Make the glass grinding faster and help the work to be completed more efficiently, which are really practical and necessary tools in your toolbox. Stained glass drills are suitable for forming and drilling of hard materials such as ceramic tiles, glass, colored glass, stone, etc. Made of quality metal material, and the surface is plated with diamonds, , high strength, and long life. Package Includes: 3X Diamond Grinder Bit Specifications: Material: metal+diamond Size: 1 Inch,3/4 Inch, 1/4 Inch note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.