Data storage devices
- 35/35.220/35.220.01 Data storage devices in general
- 35/35.220/35.220.10 Paper cards and tapes
- 35/35.220/35.220.20 Magnetic storage devices in general
- 35/35.220/35.220.21 Magnetic disks
- 35/35.220/35.220.22 Magnetic tapes
- 35/35.220/35.220.23 Cassettes and cartridges for magnetic tapes
- 35/35.220/35.220.30 Optical storage devices
- 35/35.220/35.220.99 Other data storage devices