You are bidding on a pair of RCA type 6SL7GT radio/audio tubes with round black plates.  They are new old stock, but from a bulk pack, so there are no boxes.  On my Amplitrex AT-1000 tester they test strong, and identical at 117% of the specifications for a new tube for emission, Em, and 106% of the specifications for mutual conductance, Gm on one plate.  The other plate tests as 121% Em and 106% Gm.  So they are a perfect match, and should make a great pair. They are identical, with a date code of CE.  They should be great for your amplifier.   Shipping weight is 8 ounces.  Additional matched pairs are available.  Please see my other auctions for more interesting radio and audio items, and tubes.