WD Purple 3TB Surveillance Hard Disk Drive – 5400 RPM Class SATA 6 GB/s 64MB Cache 3.5 Inch.

• Engineered specifically for surveillance security systems.
• Supports up to 180 TB/year workload rate.
• Tuned for write-intensive, low bit-rate, high stream-count applications typical to most surveillance applications.
• Prioritised write-operations for maximised surveillance performance.
• TLER & ATA streaming support.
• Support for more than eight bays