Famous American made (actually these one made in UK, but are American designed and are an American company) Acoustic Research speakers. These were a game changer in their day, lots has been written about AR speakers they had many "firsts"; inventors of the dome tweeter (dome speakers generally?) but not on these they are too early. These are still really good quality speakers and very nice to listen to. They are extremely collectable. This pair are number consecutive despite the red pen on one and black on the other! Typical of the early AR they look rough but that seems to be how they came, black "handpainted" tape over the tweeter speaker wires (there is a version with slightly different tweeters wired from behind) but when the covers are on they look great and sound fabulous even nowadays.