These PEEK sheets can be machined to tight tolerances for use in electrical and semiconductor parts, such as test sockets. Clear Scratch- and UV-Resistant Acrylic Clear Scratch- and UV-Resistant Cast Acrylic Sheets, Bars, and Cubes Cast acrylic is easier to machine than extruded acrylic. It's mparable to Lucite and Plexiglas Acrylic.