GAUGE PROJECTORS; PROFILE PROJECTORS; CONTOUR PROJECTORS; SURFACE PROJECTORS; OPTICAL COMPARATORS; OPAQUE AND TRANSLUCENT SCREENS AND CHARTS, COLOURED FILTERS, COORDINATE MEASURING SLIDES, V-BLOCKS AND CENTERS, COMPONENT FIXTURES, PROTRACTOR ATTACHMENTS, AND SURFACE ILLUMINATORS, ALL FOR USE WITH THE AFORESAID PROJECTORS AND COMPARATORS; PROBE ILLUMINATORS; LENSES; PRISMS; MICROSCOPES; PROJECTION MICROSCOPES; MAGNIFYING GLASSES; ILLUMINATING MAGNIFIERS; MIRRORS FOR OPTICAL INSTRUMENTS; MICROF...