The Western Digital Purple 4TB SATA 6Gb/s WD40PURZ ScHA500 is a high-performance internal desktop drive designed for a variety of devices including laptops, DVRs, PCs, servers, NVRs, iOS, and Android devices. With a rotation speed of 7200 RPM and a storage capacity of 4TB, this drive offers fast read speeds of up to 500MB/s. It features a temperature sensor, low noise level, and is surveillance rated, making it ideal for use in security systems. The drive is sealed for durability and has a built-in media server for added functionality. Made by Western Digital, this HDD is a reliable choice for storage needs.