9Pc Set Includes: - Aluminum Handle with Storage 7Pc Brass Collets (mm): 0.8 -1 1.3-1.5 1.8-2.0 2.2- 2.4 2.8-3.0 (2x) 3.0 - 3.2 - Cone Shape Diamond Burr Handle Length : 4-3/4" • Great for Use with HSS Drills, Diamond Burrs, Bead Reamer, Files Etc Great for Jewelers. Machinists, Artists, Craftsman, Hobbyist Etc.