IBM 3850 OnLine Tape Library

(Mass storage system 1975-1985)

The data cartridges were circular cylinders, two inches in diameter and four inches long. Cartridges were stored in a two-dimensional array of bins, which were hexagonal, rather than square, to save space.

Cartridge holds 50 Mb of data. Tape is approximately 7 cm wide and 19 m long. A1-model holding 706 cartridges storing 35.3GB.