WD Ae 6TB Hard Drive for Backup Storage - 3.5" HD, SATA 6 Gbps, 64MB Cache - WD6001F4PZ Product: Energy Efficient Datacenter Hard Drive with SATA 6 Gb/s Interface Storage Capacity: 6 TB || HD Form Factor: 3.5-inch Cache Buffer: 64 MB Data Transfer Rate (host to/from drive): 150 Mbytes/s sustained || Data Transfer Rate (buffer to host): 600 Mbytes/sec max Warranty- 1 year seller replacement warranty