Are Reel

Are Reel
With no visible labels how can you tell the difference between old 9 track and 21 track round reel tapes?

These are old round reel tapes of varying sizes that often contain data that is relevant today and thus often need to be transcribed to newer type media tapes, servers, etc.

Get a magnetic viewer. See links below.

Where the Wild Things Are, Sweaty Robot : Reel Good Show