These adapters are made from high-quality steel, hardened and tempered, precision ground inside and outside for high concentricity. The taper shank allows the tool to be inserted directly into the machine's spindle, facilitating high-torque applications such as large cut diameters. Features: - Made from high-quality 45# steel, durable, wear-resistant, and designed for long service life. - Utilizes an overall quenching process for strong shock resistance. - High accuracy and fine workmanship; internal and external surfaces are smooth. - Easy to store and maintain. Available in four types. - Compatible with taper shank cutters, taper shank drills, and taper shank reamers to improve work efficiency. Specifications: - Material: 45# steel - Type: MT1 to MT2, MT2 to MT3, MT3 to MT4, MT4 to MT5 (optional) - Hardness: 50 HRC Dimensions: - MT1 to MT2: D 17.78mm, d 12.065mm, L 92mm, External Taper MT2, Internal Taper MT1, Inner Hole Length 56mm, Weight 89g - MT2 to MT3: D 23.825mm, d 17.78mm, L 112mm, External Taper MT3, Internal Taper MT2, Inner Hole Length 67mm, Weight 174g - MT3 to MT4: D 31.267mm, d 23.825mm, L 140mm, External Taper MT4, Internal Taper MT3, Inner Hole Length 84mm, Weight 350g - MT4 to MT5: D 44.399mm, d 31.267mm, L 171mm, External Taper MT5, Internal Taper MT4, Inner Hole Length 107mm, Weight 1000g Package Included: 1 x Taper Drill Sleeve Note: Monitors are not calibrated the same; the item color displayed in photos may vary slightly from the actual product. Please refer to the physical item for accurate color.