I bought a pair of Cerwin Vega speakers at an estate sale, and these were in them. I replaced them with the correct speakers and now I'm selling these.
I don't know what they came out of, but they would make great replacement woofers, or could be used in a new build.
Note: I make no guarantee that the holes will match up with what you might be replacing. Free returns if damaged in shipping or DOA.
I offer fast, safe, and fair cost shipping. So buy with confidence.