This is a non working unit. It does not power on. Missing 1 tube. It has been in storage for around 20 years. Number on the back chassis is A33764. Number inside on an internal part is 022699 . Great restoration project for a collector. I am not sure of the exact year of this amp. Feel free to send any questions or request more photos.  I ship next business day after an auction ends. Package will be insured for purchase price. Thanks!