This WD Red™ Plus 4TB internal hard drive is designed for NAS systems with 1-8 drive bays in both 3.5" form factors. Its 4TB capacity provides plenty of space to house files, and the Serial ATA interface lets you connect your laptop or desktop. Packed with power to handle the small- to medium-sized business NAS environments and increased workloads for SOHO customers, WD Red™ Plus is ideal for archiving and sharing, as well as RAID array rebuilding on systems using ZFS and other file systems. Built and tested for up to 8-bay NAS systems, these drives give you the flexibility, versatility, and confidence in storing and sharing your precious home and work files.