CAPACITY: 4TB. Seagate SkyHawk 4TB Surveillance SATA Hard Drive w/ 5400RPM 6Gb/s 256MB Cache. Uncompromising Storage with a WD Purple Surveillance Hard Drive With an MTBF of up to 1 million hours3, WD Purple drives are engineered for mainstream surveillance DVRs and NVRs that operate 24/7.
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