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
This Audico tape timer is a handy device we use to time audio cassettes. We are looking for more of these! Let us know if you have any leads.
These heavy-duty vintage cases have no posts and are ideal for storing Dropmix cards and other small items. These are authentic 90s era cases weighing 50% more than standard cases. The back flap is only 1/2″ instead of 1 inch.
https://www.duplication.ca/Cassette-Box-With-Narrow-Back-No-Posts.html
Where can I buy the Elbow Cassette Player?
The Elbow cassette player is only a great-looking design concept! 
The design was created by the audiovisual art duo Brainmonk . The concept won design awards, however they have now announced that this product will never be made:
See more on the Elbow facebook page