Abstract: There is provided a new and useful apparatus for applying a removable protective cover to an optical disc in which the optical disc has a circular configuration, an aperture centered therein and an outer edge. The cover comprises at least one sheet of film of generally circular configuration which corresponds to the circular configuration of the disc. The cover is constructed of a material that will not adversely interfere with the read process of the disc when the cover is in place about the disc. The cover further comprises a plurality of resilient clasps spaced about a circumferential edge of the film to engage the disc about its outer edge in a snap-on spring-like fit.

Abstract: There is provided a new and useful protective cover for an optical disc of circular configuration having a circular aperture centered therein and having an outer edge. The protective cover is a sheet of film of generally circular configuration corresponding to the configuration of the disc, wherein the film is of a material that will not interfere with the read process of the disc when the cover is in place about the disc. The protective cover has a plurality of clasps spaced about a circumferential edge of the film to engage the disc about its outer edge in a snap fit.

Abstract: Apparatus for facilitating drilling or similar machining operations upon a workpiece, the apparatus including a vertically directed vee shaped recess (15) for interchangeably receiving and centring tool guide arrangements (18) for the tools required to be used for machining the workpiece; and means (19) for cramping a selected tool guide arrangement (18) against the mutually inclined faces of the vee shaped recess (15); and with a vee shaped recess (14) whose apex (17) is directed transversely of the apex (16) of the vee shaped recess (15) and intersects the apex (16) of the vee shaped recess; a workpiece support means (26) mounted for displacement towards and away from the vee shaped recess (14) in such manner that a workpiece (27) placed upon the workpiece support means (26) can be brought into firm contact with the faces of the vee shaped recess (14), and means for positionally locating a workpiece upon the workpiece support means (26).