Amazon.com: Supermicro RSC-R2UT-2E8R 2U RISER PASSIVE GEN 2-PCIE X16 TO 2X PCIE X8 : Electronics
Dual M.2 PCIe NVMe Adapter Without PCIe Splitter Function (PCIe Bifurcation Motherboard is Required), Support M.2 PCIe 4.0/3.0 SSD Soft RAID Setup in Windows/Linux
RC1PELY423-C7 PCIe dual-lanes flexible splitter from one PCIe x16 to 2-slots PCIe x16(x8 signal) - AeroCooler
Amazon.com: PCIE to U.2 Adapter Card, PCIE X16 to 4 Port U.2 NVME SFF-8643/8639 Expansion Card, PCIE 4.0 U.2 Split Card with LED Indicator for Windows : Electronics
Amazon.com: 2U Riser Card with 2 x PCI-Express 16x + 1 x PCI-X : Electronics
Pci-e 4.0 X16 1 To 2 Expansion Card Gen3 Gen4 Pcie-bifurcation Ic X16 To X8x8 Graphics/network/capture Card 20mm Spaced Slots - Pc Hardware Cables & Adapters - AliExpress
RE16LEBR-R10A Asus PCIe Riser / Splitter x16 to phy x16 & x8 | eBay