SeagateSkyhawk ST4000VX016 Internal Hard Drive 3.5" 4000 GB Serial ATA III

Seagate Skyhawk 4 TB, Video Internal Hard HDD – 3.5", SATA 6Gb/s, 256MB Cache, for DVR NVR Security Camera System, with in-house Rescue Services (ST4000VX016)

Reolink 36 Channel NVR for Security Camera, 3 HDD Bays, Support 16MP/4K/5MP/4MP Home CCTV Systems, 24/7 Surveillance Recording, Integrated O/I Alarm, RLN36 (No HDD Included)

Toshiba 4TB S300 Surveillance HDD - 3.5' SATA Internal Hard Drive Supports up to 64 HD cameras at a 180TB/Year workload (HDWT840UZSVA)