It doesn't exist. Some of the things we believe are real...are not. It's just one of those quirky life things. We have to adjust our own perceptions of reality if we are to meet our potential.

...or...

It could be when they first changed over to the B/O badge and sent some out without numbers. It was right at that transition time. I've had several drums cross my path this year with one of those badges.

1970 right? I've got another 400 with a date stamp and serial numbers from 70. No anti-galv stamp either. Weird acrolite with 400 lugs?

or

not real!

they made 70's acrolite's with imperial lugs on them. i've owned one since 1969 Cool1

Chrome acrolite?

Based on the work of a member that used to post here: In 1971-1972 Ludwig also used B & O Badges without Serial Numbers.

That was from LVDC - LudwigVonDrumCrazy

I talked to him about 4 weeks ago, and he has been doing other things.

David

The more recent B-stock supras have B/O badges... do they have serial numbers?

if you are referring to the monroe blue olive badge supra's, yes they have serial numbers

The shell is brass. I'm sure you've answered this question 8000 times but here goes again. When did they switch to Ludalloy?

Sounds like a 1970 to me. My drumset including my 400 supra all have blank badges and date stamps of 1970 inside their shells.