Amazon.com: WD Purple NV 4TB Surveillance Hard Disk Drive - Intellipower SATA 6 Gb/s 64MB Cache 3.5 Inch - WD4NPURX : Electronics
Seagate 4TB SkyHawk Surveillance SATA III 3.5" ST4000VX013 B&H
Western Digital WD4000F9YZ 4TB SATA 6Gb/s 64MB 7200RPM 3.5" Hard Drive
WD Blue 4TB Internal SATA Hard Drive for Desktops WDBH2D0040HNC-NRSN - Best Buy
Amazon.com: WL 4TB 64MB Cache 5400RPM SATA III (6.0Gb/s) (Low Power & Heavy Duty) 3.5" Internal Hard Drive (PC, NAS & CCTV DVR) - w/ 1 Year Warranty : Electronics
Synology 4TB HAT5300 SATA III 3.5" Internal Enterprise
Crucial MX500 4TB 3D NAND SATA 2.5-inch 7mm (with 9.5mm adapter) Internal SSD | CT4000MX500SSD1 | Crucial.com
WD Blue 4TB Internal SATA Hard Drive for Desktops WD40EZRZ - Best Buy
Synology HAT3300 4TB Plus Series SATA HDD 3.5" - Newegg.com
Dell 4TB 7.2K RPM SATA 6Gbps 512n 3.5in Hot-plug Hard Drive | Dell USA