An item specifically designed to be used with a multiscale dial or sector of a measuring device to limit, open or close the observation of the scale (s), or dial (s) desired. it is usually flat and contains one or more observation slots. It may be hinged or otherwise moved by rotary or straight-line motion to expose the scale or scales required for observation.
NSN 6145-01-225-1389
NSN 2925-00-126-2879
NSN 5999-01-012-1421
NSN 6645-00-960-6594
NSN 5945-01-502-7266
NSN 5930-01-048-9529
NSN 5835-01-538-8080
NSN 5945-01-343-9283
NSN 6220-01-442-9631
NSN 7035-01-287-9817
NSN 5990-01-472-2447
NSN 5895-01-608-0562