Western Digital Red Pro 3.5 Inch 16TB Serial ATA HDD Designed specifically with medium or large scale business customers in mind, WD Red™ Pro NAS HDDs are available for up to 24-bay NAS systems. Engineered to handle high-intensity workloads in 24x7 environments, WD Red™ Pro is ideal for archiving and sharing, as well as RAID array rebuilding on extended operating systems such as ZFS or other file systems. These drives add value to your business by enabling your employees to quickly share their files and back-up folders reliably in your NAS solution.