Designed for high precision CNC machine or heavy duty bench machine. Mounted with 3MT morse taper No. 3 shank for convenient quick change in operation. One set of solid steel internal jaws, one set of solid steel external jaws, and chuck wrench are also included in the package. Body is made of high quality semi steel. All pinions and jaws are harden to Rc 60-62. PLEASE NOTE THE MORSE TAPERED CHUCK PLATE IS NON-ROTATING. Shank Size: Morse Taper #3 MT3. Max RPM: 4,800. All of our products are 100% inspected. All of our products are in brand new condition. If you have any questions regarding our products or services, please give us a chance for correction. Please do not leave a negative or neutral feedback. We will do our best to fix it.