Use 2.5' 9.5mm height SATA hard drive for ND2730.

Recommend using 7200rpm HDD if you using CF for best performance.
Recommend using 5400rpm HDD if using SD to save battery power during copy.

SATA hard drive from Hitachi is not recommended because of slower copy speed.

SATA hard drive from following company tested working well with ND2730.
- Seagate
- WesternDigital
- Toshiba
- Fujitsu

SSD also supported but only the one from SAMSUNG was tested.