Abstract: An apparatus for cutting and shaping a material is disclosed which includes securing means for securing an adaptor having a lens blank or a semi finished lens is fixed thereto to apparatus for working. The securing means comprises a generally cylindrical housing having first and second ends and a throughbore, the first end having a plurality of axial slots defining a plurality of finger-like members which can act as a collet. A piston is disposed within the throughbore and is axially movable therein, the piston being connected to a sleeve member which is mounted so that it surrounds the plurality of finger-like members. The securing means further comprises means for moving the piston relative to the housing and means for defining a sealed fluid chamber between the piston and the piston moving means.