Seagate ST31000524NS 1TB 7200RPM SATA II 3GB/s 64 MB Cache 3.5" Enterprise Hard Drive (PC, RAID, NAS, CCTV DVR) [Certified Refurbished] -w/1 Year Warrany This Certified Refurbished product is tested and inspected to look and work like-new, with limited to no signs of wear. The product comes with relevant accessories and a minimum one-year warranty. 1TB Capacity, 7200RPM Rotation Speed, 32MB Cache 3.5" Internal Hard Drive, SATA II 3.0Gb/s, Enterprise Grade, Heavy Duty Works for PC, NAS, NVR, Surveillance CCTV DVR Passed Factory Diagnostic Software + RE-CERTIFIED by State-of-the-Art software - Full "Sector-by-Sector" test to ensure best HDD quality! ZERO Bad Sectors!