FMC carriers typically have FMC site(s) on them, a large user FPGA and either links to an external host or an onboard host. The carriers that are plug in boards, the PEX6-COP plugs into a desktop PC PCIe slot. The SBC-K7 has a COMexpress host CPU and can be supplied on its own or in a case (ePC-K7) or a smaller version can be supplied as the mini-K7. The mini-K7 can also be supplied rugged. Sites are either HPC (high pin count) or LPC (low pin count).