The HP440 Collet Set is for use with H.43T, H.44, H.44T, H.44TSJ and H.44HT collet-style handpieces. It is also for use with BL Bench Lathe Adapters A-CHA-4 and A-CHA-5. This set adds great versatility since it accommodates different diameter shank burs and other accessories. The set includes these seven fractional and metric sizes: Collet HP442 3/32” Collet HP448 3mm Collet HP443 1/8” Collet HP445 3/16” Collet HP444 5/32” Collet HP449 6mm Collet HP447 1/4” Individual collets can be purchased separately.