For sale is one of my two beloved 596 rectifiers with adapter to be used anywhere a 5U4G is required. You can read up on this forum about what an amazing replacement this is. This tube is in great condition with many many hours of wonderful music left in it. I have not tested it but I bought it NOS and put between 100-200 hours on it tops. Nonethelss, all I can do is guarantee it's not DOA but beyond that, buyer beware, as always with tubes. Buyer to pay shipping and fees. If you are interested in a pair, I would consider offers for this and other 596 I am listing. Cheers and thanks for looking.