Written in very faint marker on opposite the hub; possibly a LLL deprecated accession number.
overall: 1 3/8 in x 26 in x 26 in
This is a magnetic disc 26" total diameter with a 9.25" uncoated exposed metal center, to which is bolted a 8.25" diameter hub using four bolts that pass from the other side of the disc. The hub is slightly more than 0.25" thick, with a 0.5" thick extension that is 0.5" wide and 6" outside diameter. There is a 3" diameter hole through the center of the disc for the hub; the hole is surrounded by four 0.5" diameter holes.
Memory & storage/disk
Gift of Lawrence Livermore National Laboratory (LLNL)