Features: WD Red is designed specifically for small NAS systems that have 1 to 8 drive bays. The drives are designed and extensively tested for compatibility in the unique 24x7 operating environment and for the demanding system requirements of home and small office NAS.

Storage for 1 to 8 bay NAS solutions - WD Red is designed specifically for NAS systems that have 1 to 8 drive bays in both 3.5-inch and 2.5-inch form factors. The drives are designed and extensively tested for compatibility in the unique 24x7 operating environment and for the demanding system requirements of home and small office NAS.

NASware grows to 3.0 - WD Red now supports small NAS systems from 1 to 8 bays thanks to NASware 3.0, which further improves drive compatibility and reliability. At 48TB of total capacity in an 8 bay system, WD Red expands your NAS experience.

3D Active Balance Plus - Our enhanced dual-plane balance control technology significantly improves the overall drive performance and reliability. Hard drives that are not properly balanced may cause excessive vibration and noise in a multi-drive system, reduce the hard drive life span, and degrade the performance over time. (EFRX models only)

WESTERN DIGITAL RED WD40EFRX 4TB INTELLIPOWER 64MB CACHE SATA 6.0GB/S 3.5" INTERNAL HARD DRIVE