Features: Perfect for surveillance DVR, NVR, and SDVR. Support each system up to 8 drives(4TB is above 8 drives) and each drive supports 64 cameras. 7*24 work mode and mean time between failure(MTBF) with 1 million hours. Specialize design for a workload of 180TB per year which is 3 times the support of a desktop drive. Minimize the consumption of heat and vibration, thus improve the long-term reliability of hard disk. Precision-tuned for high write surveillance workloads. 7200 RPM on all capacities except for 4TB(5900 RPM). Surveillance optimization specialized HDD, accurate calibration can realize all-weather operation, high in surveillance work load.