c-90.org is a thing of wonder, not least for the Catalogue of Tapes, each lovingly photographed and organized by brand.
This page is dedicated to cassette tapes. Here you won't find any kind of scientific research, technical data or things like that. The authors' only message is just to give a visitor something interesting to look at. The era of this particular medium is slowly passing, and here we are trying to turn back time for 60 minutes, or, maybe, for 90…
Pictured above is the Sony C-1C Head Cleaner. Sadly, the image sizes are rather small.