1FT278-031 - EMC 4TB 7200 RPM SAS 3.5" HDD for Unity 300, 400, 500, 600 serie... | eBay
HGST 4TB 7200 RPM SAS 3.5" HDD for DS4246, DS212C, FAS2620 0F22948 | eBay
Amazon.com: WD 4TB 7200 RPM SATA 6 Gb/s 64MB Cache, 3.5-Inch Desktop Hard Disk Drive (WD4003FZEX) : Electronics
Seagate FireCuda 4TB 7200 RPM SATA III 6Gb/s 3.5" Internal CMR Hard Drive - Micro Center
Seagate Enterprise Capacity 3.5'' HDD 4TB 7200 RPM 512e SATA 6Gb/s 128MB Cache Internal Hard Drive ST4000NM0115 - Newegg.com
WD Red Pro WD4003FFBX 4TB 7200 RPM 256MB Cache SATA 6.0Gb/s 3.5" Internal Hard Drive Bare Drive - Newegg.com
Amazon.com: HP 695842-001 4TB SAS Hard Drive Disk (HDD) - 7,200 RPM, 3.5-inch form factor, SmartDrive Carier (SC), Midline (MDL), 6Gb per second Transfer Rate (TR) : Electronics