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 6685-01-368-4611
NSN 6110-01-143-9296
NSN 6220-00-973-9416
NSN 5950-00-954-3801
NSN 5998-01-369-0559
NSN 2925-01-408-6205
NSN 6150-00-741-2539
NSN 5835-00-532-5910
NSN 5935-00-627-4332
NSN 2925-01-244-3016
NSN 6620-01-029-3705
NSN 5975-01-346-7194