You are bidding on a pair of Electro Harmonix Type 6973 EH radio/audio output tubes.  These are new old stock in original but written upon boxes.  On my Amplitrex AT-1000 tester they test strong, one at 98% of the specifications for a new tube for emission, Em, and 92% of the specifications for mutual conductance, Gm.  The second tube tests at 95% Em and 8691% Gm.   So they are closely matched, and are good usable tubes. They are identical.  They should be nice tubes for your amplifier.   Shipping weight is 8 ounces.  Please see my other auctions for more interesting radio and audio items, and tubes.