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 6135-01-463-2445
NSN 5950-01-410-8776
NSN 5975-01-005-8774
NSN 6620-01-571-0900
NSN 5985-01-599-5951
NSN 5965-01-372-3593
NSN 6645-01-422-8078
NSN 5910-01-076-7632
NSN 5835-01-632-6627
NSN 4140-01-399-3027
NSN 6130-00-600-1971
NSN 5996-00-557-8902