Product Name: Bt Er Milling Bt Tool Holders for CNC Machining Center Model NO.: BT-ER Certification: ISO 9001:2008 Material: 42cr Type: Cutting Tool Customized: Non-Customized Size: Middle Logo Printing: Without Logo Printing Hardness: HRC48-50 Accuracy: 0.005mm Application: CNC Machining Center, CNC Machining Center Taper Tolerance: At3 Trademark: PERFECT Transport Package: Paper Bag Specification: JIS MAS403 Origin: China Jiangsu HS Code: 8466100000 Product Description Spindle conicity standard:JIS MAS 403 BTER collet chuck set with ER collet with flexibility used for gripping cutting tool, drill bit, draw bolt and so on.When using, nut should be clamped tensed firstly with cutting tools then locked into the main body.Always use the recommended wrench or spanner, unless, there might cause damage of cutting tools.The spanner,pull stud chuck must purchase alone.