1 lx 5 months ago NFI.Unfortunately, this 6196 #26199 was "re-wired" for mono use, but the strange white bobbin Filtertrons with unusual pole-piece configuration are no doubt original. The label also reads "projecto-sonic SPC". There is also a word/notation on the Dan Duffy signed ok card which might read "cleanness"(?) Perhaps this was an early and as yet undocumented iteration as it has standard Filtertron spacing and a Melita. Too bad about the binding rot.