OWC Accelsior 1A Apple Factory SSD to PCIe Adapter Card
Adapter, U.2 to PCIe - 2.5' U.2 NVMe SSD - Drive Adapters and Drive Converters
Amazon.com: Sedna PCI Express (PCIe) SATA III (6G) SSD Adapter with 1 SATA III Port (with Built in Power Circuit, no Need SATA Power Connector, Best for Mac), SSD not Included :
Amazon.com: Sedna - PCI Express (PCIe) Dual 2.5 Inch SATA III (6G) SSD Adapter (Short Double Side SSD Version) (with Built in Power Circuit, no Need SATA Power Connector, Best for Mac),
RIITOP NVMe Adapter M.2 PCIe SSD to PCI-e x4/x8/x16 Converter Card with Heat Sink for M.2 (M Key) NVMe SSD 2280/2260/2242/2230 mm - Newegg.com
WD 2.5in NVMe/PCI E SSD to M.2 NGFF PCIe x4 SSD Adapter Enclosure PCI Express SSD Adapter Card - Walmart.com
U.2 SFF-8639 NVMe SSD to PCI-e 4X Adapter - Walmart.com