Product description
The M.2 2×2 card, provides two M.2 PCIe Gen 3 x2 lanes connectors, from the PCIe Gen 3 x4 lanes of the mainboard. It allows you to use two M.2 devices: any combination of NVMe drives, Network adapters, WiFi adapters, 5G adapters, etc that leverage the bandwidth of PCIe Gen 3 x2 lanes.
More information is available on the website of Hardkernel.