no, they are like the good ones. they look just like the cetron with the same plate type and everything else.
these were the ones actually http://www.ebay.com/itm/1-PAIR-BECKMAN-6336A-TUBES-TESTED-/221298393829 if u click on the picture once or twice, it'll take u to the original thingy and u can see more pics of them.
Did the one of the right died? Look at the white stuff on the right tube, it seems melted compared to the left one. I had some rare CSF 6336A DOA and just put them in a box of collected dead tubes. Some 5998 die easily too.