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 5855-00-149-0766
NSN 6650-00-059-6268
NSN 6685-01-441-7568
NSN 5999-00-368-8428
NSN 6220-01-554-8968
NSN 5990-00-828-1771
NSN 6620-00-257-2783
NSN 6105-01-519-8003
NSN 5960-00-687-1031
NSN 5945-01-443-3423
NSN 5925-01-007-6368
NSN 6645-01-384-7791