WESTERN DIGITAL ULTRA 8TB 3.5 INCH HDD 256MB 7200 ENTERPRISE

Built for 24/7, always-on, high-definition security systems. With a supported workload rate of up to 180 TB/yr and support for up to 64 cameras, WD Purple drives are optimized for surveillance systems.

WD Ultrastar HC330 10TB Enterprise Hard Drive SATA 6Gb/s 7.2K RPM 256M 0B42266 512e/4KnSE 5 Years warranty WUS721010ALE6L4

Seagate SkyHawk 2TB SATA3 HDD , durable reliability and performance tuned to the high-write workloads of today 24Hours&7days video surveillance systems ( 3 years warranty )