The WD 4TB WD40EFPX  Red Plus NAS HDD offers exceptional performance with a 7200rpm speed, 256MB cache, and SATA 6Gb/s interface rate, making it ideal for server applications. Featuring a robust metal shell and an average seek time of 8.9ms, it ensures durability and efficiency. With read/write speeds of 601-700MB/s and a noise level optimized for NAS use, this internal hard drive is reliable for demanding storage needs.