What in the Hell Is a Tefifon?

Whoa. Have you guys EVER seen/heard/owned a Tefi­fon? Nope?! I didn't think so! The Tefifon was a German-engineered and -manufactured tape deck that used cartridges "loaded with an end­lessly looped reel of plas­tic tape (much like the later 4-track and 8-track mag­netic audio tape car­tridges) with grooves em­bossed on" the tape surface. So, tho' it was a tape, instead of sound stored magnetically, it had grooves like what we see on records.The grooves were em­bossed in a he­li­cal fas