1. High quality elastic steel material with long use time.
2. Type: A AD AD/B
3. Shank of the Arbors:BT30, BT40, BT50, DIN69871.A30, DIN69871.A40, DIN69871.A50, CT40, CT50. DIN2080
4. The precision little than 0.005mm with balance 8000rpm. Higher precision also can be made by your demand. (G6.3/12000rpm, G2.5/20000rpm)
5. Holder hardness: HRC 52-55