Western Digital 4 TB WD Purple Surveillance Internal Hard Drive HDD SATA 6Gb/s 256 MB Cache, 3.5 Inch (New in Package)

Engineered for mainstream surveillance systems
WD AllFrame technology delivers optimizations for write-intensive, low bit-rate, high stream-count workloads typical to mainstream surveillance applications
Supports up to 180 TB/yr workload rate(3) | (3) Workload Rate is defined as the amount of user data transferred to or from the hard drive. Workload Rate is annualized (TB transferred u2715 (8760 / recorded power-on hours)). Workload Rate will vary depending on your hardware and software components and configurations.
Support for up to 16 bays(7) | (7) 1TB through 2TB support up to eight bays; 3TB and above support up to 16 bays.
Tarnish-resistant components(6) | (6) Tarnish resistant components for capacities 3TB and higher.