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 5915-00-147-8931
NSN 5998-01-363-7077
NSN 5925-01-539-4052
NSN 5996-01-467-2177
NSN 5925-00-379-0920
NSN 5910-00-245-0940
NSN 6645-00-140-5173
NSN 7035-01-551-1240
NSN 6105-01-521-7420
NSN 5950-01-398-0762
NSN 6645-01-370-5264
NSN 6320-01-501-7935