Lathe Milling use -- HRC58 taper shank drill sleeve has high precision, smooth inside and outside, easy to store and maintain.craft -- The MT1- MT2 MT2- MT3 MT3- MT4 taper adapter adopts the quenching process as a whole, which has strong impact resistance.application -- High hardness taper shank drill bit can reduce reamer.45 # steel -- The tapered adapter set is made of high-quality 45# steel, which is not easy to rust and can be used for a long time. use -- HRC58 taper shank drill sleeve has high precision, smooth inside and outside, easy to store and maintain. craft -- The MT1- MT2 MT2- MT3 MT3- MT4 taper adapter adopts the quenching process as a whole, which has strong impact resistance. application -- High hardness taper shank drill bit can reduce reamer. 45 # steel -- The tapered adapter set is made of high-quality 45# steel, which is not easy to rust and can be used for a long time. Specifications: Model: 1-2 2-3 3-4 Hardness: HRC58 Size: MT1- MT2: length: 92mm / 3.62in, bottom hole diameter: 12mm / 0.47in MT2- MT3: length: 112mm / 4.41in, bottom hole diameter: 17mm /0.67in MT3- MT4: length: 133mm / 5.24in, bottom hole diameter: 23mm /0.91in Weight: 569g colour:Silver Material:metal Package Contents: 1 x MT1- MT2Taper Adapter 1 x MT2- MT3 Taper Adapter 1 x MT3- MT4 Taper Adapter Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.