TK16
Headphoneus Supremus
The ones you have from Upscale Audio looks fake to me, sorry to say that. This one I could see clearly the o = a 0 (zero) bigger than the rest. And the numbers are not alligned well. Difference between hand marked or machine marked.
The ones I linked from eBay are harder to see, looks legit to me. I cannot spot a mistake. When I look at the pins on the eBay ones they are not completely straight. Also I see the square on the bodem on the eBay one (which is both good). The box (number) and used label on the eBay tubes I could not verify good enough on the pictures. I think only the Telefunken with vertical-datecode have a date-code on the box as well. But I can't do yet a water check for example. But yours is clearly easier to identify than the one on eBay. I did send two-mails to the seller and confront him and asked him to provide more information about the tubes (batch) and if he did know about being fake telefunken on the market. And if he could spot the difference. I don't want to harm his reputation, neither I want to receive fake tubes. So I gave him a friendly warning and told him that a close friend (Tube-expert) will set his eye on them as well.
see here for example of the fakes:
Just for your information: I did e-mail Upscale Audio Twice (about shipping internationally). Would pay for the extra costs etc.
No response so far.
I have made 3 successful trades here, 1 for a big ticket item without a hitch, I would not appreciate being called out on trading "fakes" with that tiny bit of info you posted and I'm sure the other headfier does not either. Now you injected doubt in a sale of likey real Telefunken E88CC.