When the TS1140 uses a partial tape for output, the existing data on tape may be in the EFMT3, EEFMT3, EFMT4, or EEFMT4 recording technologies. The tape will be extended in the same format. The choice of the correct recording technology will be transparent to DFSMShsm. MEDIA10 and MEDIA12 tapes are normally (unless patched by the customer) used only by ABARS and only as scratch tapes. MEDIA11, MEDIA12, and MEDIA13 partial tapes are always recorded using EFMT4 or EEFMT4 technology.

Earlier technology 3592 drives might use MEDIA9 and MEDIA10 partial tapes. DFSMShsm checks the recording format already on the tape against the capabilities of the drive to ensure the drive is capable of extending the tape. If not, DFSMShsm rejects the partial tape.