Asus HYPER M.2 X16 GEN 4 CARD Hyper M.2 x16 Gen 4 Card (PCIe 4.0/3.0) - Newegg.com
The Dell 4x m.2 PCIe x16 version of the HP Z Turbo Quad Pro
High Speed 32Gbps M2 PCI-E NVMe SSD to PCIe 3.0 X4/X8/X16 Adapter Card Converter | eBay
ASUS Hyper M.2 X16 PCIe 3.0 X4 Expansion Card V2 Supports 4 NVMe M.2 (2242/2260/2280/22110) Upto 128 Gbps for Intel VROC and AMD Ryzen Threadripper NVMe Raid
Amazon.com: ELECTOP NVME PCIe x16 Adapter, M.2 Key-M SSD to PCI 3.0 Express Expansion Card, Support 2230/2242/2260/2280 with Heat Sink, Compatible with Windows XP / 7/8 / 10 & MAC OS System : Electronics