These are two identical Sony FeCr used audio cassette tapes from 1979 in original tape cases. Tapes are 90 minutes, Type III, made in Japan.

Both cassettes are clean, in acceptable condition with wear: shell stickers have some damage, writing, and correction fluid marks. J-cards also have writing and correction fluid marks. Tape cases have some scuffs (no cracks).

You will receive two cassette tapes as seen in the photos.

If you are not familiar with Type III tapes, the first thing to note is that they were available for a relatively short period between the mid-1970s and the early 1980s. 

Type III Ferro-Chrome tapes pre-dated Type IV metal cassettes, and were developed to rectify the problems inherent in the two previously existing cassette types (I and II). Type I ferric-oxide tapes had poor definition in the higher treble regions, while Type II chrome tapes had a relatively weak bass response. The concept with the Type III was to combine, on the tape coating, a layer of ferric-oxide with a layer of chromium-dioxide. Theoretically, this would offer the user the enhanced high frequency definition of chrome, plus the fuller bass of the regular ferric tape.