The stamper code is CDR UG 90 I451410 KJRY
with some art of symbol near KJRY
No serial number
AFAIR I read somewhere that they are from SKC (?)
They only work in 1 of my 4 CD Players.
The Datatrack and Cockmedia 99min CDs work in all my players, the MediaRange Vinyl 80min CDs with the same amount of errors as the MediaRange 90min work everywhere, too.