These centers are used when you need to spin large diameter of pipe of hollow work. Manufactured from high quality tool steel grade 8620 Heat treated for hardness up-to 58+/- 2 HRC Precision ground, the head revolves on a double bearing set up, which includes ball & taper one. Pipe holding diameter capacity: 2" (50 mm ) to 3" (75 mm). Available in MT2 & MT3 shanks.