One super useful feature was "Auto Reverse", allowing you to listen to both sides of a tape without having to take the cassette out and flipping it. It came out

One super useful feature was "Auto Reverse", allowing you to listen to both sides of a tape without having to take the cassette out and flipping it. It came out 3 years later, eg in the Sony WM-7. One thing I learned while looking into this now is that Music Cassettes (MC) have the magnetic recording tape, and then at both ends a "leader", which is much stronger than the thin magnetic tape, so it doesn't break when the end is reached. Furthermore, the leader is transparent, unlike the magnetic tape, and so auto reverse could be triggered by an optical sensor (this website claims that the WM 7 had an optical sensor - I thought Walkmen (Walkmans?) triggered auto reverse from the mechanical pull when the tape reached the end.) http://www.walkmancentral.com/products/wm-7 http://www.walkmancentral.com/products/wm-7 EDIT to add: https://en.wikipedia.org/wiki/Cassette_tape#Tape_leaders https://en.wikipedia.org/wiki/Cassette_tape#Tape_leaders