Features HIGH SURFACE HARDNESS: Adopt 20CrMnTi steel material, quenched and hardened, possess high surface hardness and strong wear resistance FINE CONTROL PROCESSING: The inside and outside of the tool holder are integrally formed. Fine control processing bring more stable performance and high concentricity HIGH ACCURACY MACHINE TOOL PROCESSING: After inner hole ground treatment, suitable for high accuracy machine tool processing and has a longer life than ordinary tool holders CARBURIZING AND QUENCHING PROCESS: Adopt carburizing and quenching process, the hardness is higher, the fatigue resistance of the interface is stronger and more durable 0.005MM HIGH ACCURACY: The clamping range from 1‑7mm, and the accuracy is equal or less than 0.005mm, very trustworthy. 10000rpm speed can realize fast operation Specification: Item Type: CNC Tool Holder Product Material: 20CrMnTi + carbon steel Product Model: BT30-ER11-70 Tool Handle Taper: 7: 30 Chuck Specification: ER11 Clamping Range: Approx. 1 ~ 7mm / 0.04 ~ 0.28in Tool Handle Working Length: Approx. 70mm / 2.76in Accuracy: ≤0.005mm Hardness: >HRC56° Speed: 10000rpm Rough Surface: ≥0.8mm Package List: 1 x Tool Holder 1 x Wrench 1 x Storage Box Note: Please select according to the installation specifications. Package List 1 x Tool Holder 1 x Wrench 1 x Storage Box