Specifications:Features:- Nickel bonded diamonds.- These high speed diamond coated cutting discs can be used with your rotary tool to cut a wide variety of materials.- Cut wood, glass, plastic, metal, marble, masonry, stone, concrete, and fiberglass.- For use in tight places and for flush cutting.Material: Nickel plated steelShank size: 38mmDisc diameter:50mmMax Speed: 20,000 RPMNOTE: Please add water for coolant when using diamond tools.Package Weight : 42 G / 1.48 OuncesPackage Dimensions (L*W*H) : 50*50*20 MM / 1.97*1.97*0.79 InchesRetail Packaging: No, No PackingPackage Include:5 X 50mm Diamond Cutting Discs1 X Drill Bit