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 6240-01-606-6470
NSN 2925-00-623-0262
NSN 7035-01-548-1864
NSN 6110-01-659-8833
NSN 5935-01-199-4443
NSN 5905-00-436-1398
NSN 5990-00-831-4421
NSN 6220-01-227-5364
NSN 5975-01-124-9966
NSN 5945-01-224-7272
NSN 7035-00-455-7666
NSN 5915-01-108-4552