They are, as the listing states, Infinity Monitors, the predecessor of the Monitor II and IIa, which were four way with the addition of a dome tweeter. I owned a pair in the mid-70's as well as a pair of Monitor IIa's which I still have. The original woofers were of the doped paper cone variety that Infinity used in a number of models during that period including the 1001, 2000II, and Monitor Junior. The grills on the original Monitors were a front to back wrap around foam sheet that was susceptible to foam rot and so eventually just disintegrated. They were replaced with a conventional frame and cloth front and rear grill on the II's and IIa's.
I bought a pair of Monitors pretty cheap earlier this year on eBay to get the woofers and Walsh tweeters for spares for my IIa's. The mid-domes are different having a metal grill over the dome instead of the more recognizable open dome of the later models that was also used in the Quantum line. They are not larger but just appear so because of the grill.The cabs were trashed so I asked the seller to pull and ship the drivers, which he did.
$200 seems like a lot for these with the Walsh tweeters being the only thing of any value, although I've seen Walsh pulls in good condition go for that.
