If you go to Tubemonger.com he has a library of tube pictures to compare it to. Also if you upload a picture on Audio Asylum's Tube Asylum, and ask for an ID, I bet you will get your answer. I wouldn't be too dissapointed if it turns out to be a relabled East German or RFT tube which were commonly relabled in the 70s for numerous manufacturers.
Anyone familiar with the Ultron ECC88 tube?
The only information I have is Ultron was a W.German company that distributed other manufactures' tubes. The tube in question is labeled with a Ultron logo and made in Germany beneath the logo. The seller claims it looks like an early 70's Siemens ECC88 gray shield version. Has anyone seen or more importantly heard this tube? All comments and thoughts are much appreciated.