Never use 120s. Plastic cases held together with screws are preferable in the event they must be dismantled because of tape snarl. Other types of tape, made of various formulations, are not needed for oral history interviews. All are important factors in minimizing problems. If possible, make large or frequent purchases to receive a retailer's discount price.
Cassette tape is inadequate for long-term storage and as a preservation medium.
Cassette tapes offer great convenience in recording, storage, and playback. They are compact, easy to use, and they offer reasonable fidelity for many applications, particularly for the recording of speech. They are not suited, however, for long-term storage. Any material contained on cassettes for which long-term preservation is important must be transferred to 1.5 mil. Tape other than 1.5 mil.