Designed for PC, the Western Digital (WD40EFRX) Hard Disk Drive comes with a 3.5" (Network Attached Storage). Its buffer size of 65536 KB and a massive 4000 GB storage space allows you to conveniently store plenty of work-related documents, music files, movies, games and more. Operating on a spindle speed of 5400 RPM, this HDD coupled with 6-Gb/s SATA interface offers quick and efficient transferring of data between this internal drive and other devices on the network. The Western Digital (WD40EFRX) model comes in red and renders seamless performance.