What are prison tapes?

Audio cassettes remain a popular method of distributing music and spoken-word content in prisons.

Tab-In Prison cassette shells are totally transparent with clear liners, and are sonic-welded (no screws).

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Here’s a link where you can order any length of cassette up to 110 minutes:

https://www.duplication.ca/Blank-Prison-Cassette-Tapes.html