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 5998-01-100-3919
NSN 6685-01-343-2955
NSN 2925-00-371-2285
NSN 6130-01-170-4059
NSN 5945-01-256-4133
NSN 6135-01-301-8776
NSN 5965-00-448-9923
NSN 6110-00-557-8631
NSN 6645-01-243-3138
NSN 6685-01-386-6547
NSN 5905-01-614-5713
NSN 5950-01-022-5140