$4 Orange Pi 4/4B PCIe Expansion Board Includes an mPCIe socket, and a SIM card Slot

Rockchip RK3399 based Orange Pi 4 & 4B boards launched last year with a PCIe connector. But the PCIe interface is available via a 24-pin FPC connector, not quite a standard like a PCIe slot or mPCIe socket, and hard to use for most projects as you'd need to make your own PCIe adapter board.

But it's now become much easier to use the PCIe interface as Shenzhen Xunlong Software has now launched a $3.90 expansion board connecting to the 24-pin FPC connector, and allowing users to connect mPCIe cards, especially the ones for 3G/4G connectivity as a SIM

The full article can be found @ https://www.cnx-software.com/2020/01/06/orange-pi-4-4b-pcie-expansion-board-mpcie-socket-sim-card-slot/