This drive was originally in an external enclosure.  Other than the labels,,, it is the same as the Compaq 258266-001.  Save a few bucks and order this instead.

The new HP StorageWorks SDLT 320 GB Tape Drive extends the advantages of an SDLT-based data protection solution by increasing capacity and performance by 45%. Total costs of ownership are significantly lowered by reducing the number of data cartridges required and by shrinking the backup window for business-critical data. In addition backward-read compatibility to existing DLT and SDLT-based solutions provides the highest level of investment protection while offering a smooth transition path to new SDLT 320-based data protection solutions.
The SDLT 320 is an enhanced version of the SDLT 110/220 tape drive offering a 45% increase in native capacity per cartridge (160 GB) and data transfer performance (16 MB/s). The new SDLT 320 offers the same backward-read compatibility to current DLT tape drives as the SDLT 110/220 but is also write-compatible with the SDLT 110/220 and utilizes the same SDLT1 media and cleaning cartridge.