30 New Diamond Coated Burs Files & Mandrel. 20 Burs. This is a new set of 20 diamond coated burs. These are 150 grit. This master diamond bur set allows you to shape, grind and finish with precision. Great for filing glass, ceramics, tile, brick, plastics, wood, fiberglass, stone, rock carbide, gold, platinum, silver, metals or anything else that is hard. Recommended for jewelers, lapidary, hobbies and crafts, modeling, home repair, etc. Assortment includes various sizes of round, cone, inverted cone, tree, bud, cylinder and knife edge burs. Provides uniform cutting on wide a variety of materials. Use water for lubricant. All have a 3/32 (2.5 mm) shank. 5 Cutting Wheels & Mandrel. This is a new set of 5 diamond coated cutting wheels and mandrel. Longevity is assured as the diamond particles are electroplated onto the surface of the metal. These are all medium grit for cutting or sanding stones and glass. Each cutting wheel measures approximately 3/4 (19 mm) in diameter. The mandrel has a 1/8 (3 mm) shank. 5 Files. This is a new set of 5 assorted diamond coated needle files. Cut quickly on both the push and pull strokes. Files cut stones, gold, silver and hardened and tempered stainless steel. Each measures approximately 5 1/2 (140 mm) long.