Western Digital WD Blue SN580 1TB M.2 2280 PCIe Gen4 x4 NVMe 1.4 Internal Solid State Drive, Up to 4150 MB/s Sequential Read, 4150 MB/s Sequential Write, 600K IOPS Random Read, 750K IOPS Random Write, 600 TBW Endurance, nCache 4.0 Technology