I recently got another nice vintage rod. I bought it as I wanted its cork handle, but the rod blank is also nice, much nicer than I expected.
When I was checking my old rods, I found a difference in logos printed on Phillipson 3M rods. These Phillipson 3M rods (below) were manufactured in the early 1970s. The top and middle are marked 'Rod Blank'. The bottom one says 'Epoxite Blank'. I guess this difference derives from how they sold the rods (blanks). When they sold blanks for custom-building, they seemed to use a logo of 'Rod Blank', while when they finished rods by themselves for markets, they used logo mark of to show series name such as 'Master', 'Bass Tamer', 'Swamp Fox', or just 'Epoxite Blank'.
I hear their rods in 3M era are much more popular than older ones, but to be honest I prefer older Tobacco fiber ones.