What is U.2 SSD (formerly SFF-8639)? | Definition from TechTarget
OWC 16.0TB U2 Shuttle 3.5-inch NVMe U.2 SSD at MacSales.com
PCI Express 2.5in. NVMe SSD Adapter - Drive Adapters and Drive Converters | StarTech.com Europe
U.2 - Wikipedia
Amazon.com: StarTech.com M.2. PCI-e NVMe to U.2 (SFF-8639) Adapter - Not Compatible with SATA Drives or SAS Controllers - For M.2 PCIe NVMe SSDs - PCIe M.2 Drive to U.2 Host Adapter -
Cryo-PC Full Speed NVMe SSD PCIE PCI-Express 3.0 X16 to U.2 Adapter Converter Card Module New - NWCA Inc.