Help on Telefunken tubes

Hi, My problem is this: I have a tele tube that has most of the label wiped off. I need to know if it's a ax7 or au7. I have other ax7's but this tube in question looks just like the others. It is a smooth plate and I don't know if au7's come in ribbed and smooth plates. One thing I did notice is that the little pins at the top of my ax7's look the same. The tube in question does not.Could that be an indication? Any help would be a life saver. Thanks in advance, Bret (BTW I don't have a tube tester)