At 150mm diameter, these jaws allow you to reverse chuck smaller workpieces quickly and securely at the turn of a chuck key. The conical rubber buttons pull your work gently back against the aluminium jaw plates without damaging its edge. You can use them externally or internally. A series of tapped holes offers you a variety of diameters. It is also possible to grip odd shaped pieces using different holes. The jaws come with rubber buttons. They will fit the SK80, SK100 or SK114 chucks. As an alternative to using the buttons, stacking turn studs are available as an optional extra. They form an excellent primary holding method for all manner of round or square blanks and, give a very secure grip. The studs can be used singly or doubled up using the longer bolts supplied. Recommended maximum speed 1,500rpm.