"Things You Wouldn't Know If We Didn't Blog Intermittently."
"Univac 9000 Series disk cartridge prototype with a 2.2 MB capacity 1966"
I never dealt with those, but the first hard drive I ever worked with was a 5 MB cartridge about the same size (though round), for a DEC VAX 11/750
Ah, yes. The bad old days.
Found some more info on what might be the original of this image:"1966 Univac 9000 Series disk cartridge prototype, 2.2 MB capacity. Considered too expensive at the time, the technology used to develop this ended up as Univac’s 8400-series disk pack, which held four platters in a large removable drop-in cartridge the size of a washing-basket – the first removable disk based storage system to reach market, in 1971."- http://charliedillon.org/post/142312830280/1966-univac-9000-series-disk-cartridge-prototype