Western Digital Purple 2TB 5400 RPM Surveillance Desktop Internal Hard Disk Drive ( WD20PURZ )

Engineered specifically for surveillance security systems
Supports up to 180 TB per year work load rate
Prioritized write-operations for maximized surveillance performance
Support for more than eight bays
Tuned for write-intensive, low bit-rate, high stream-count applications typical to most surveillance applications
TLER and ATA streaming support
Tarnish-resistant components