The WD Ultrastar DC SN655 is a data-centre-grade enterprise NVMe SSD, not a consumer drive — Western Digital's Ultrastar DC line is built for servers and storage arrays where sustained throughput, endurance under continuous write load and predictable latency matter more than headline sequential speed. This SE (storage/entry or standard-endurance) variant is a 15.36TB unit, a capacity aimed at dense storage nodes, hyperscale deployments and enterprise SANs consolidating large amounts of data per drive slot. It uses the NVMe interface (typically U.2/U.3 in this product family) for direct PCIe connectivity rather than a SATA/SAS bottleneck, and is designed for 24/7 operation with the higher write-endurance and power-loss protection features expected of enterprise storage. Exact interface generation, form factor and DWPD endurance rating aren't stated in the listing and should be confirmed against WD's datasheet for the exact part number before specifying into a server build.