The Matt Card is the alternative to swapping the EFI ROM chip on your motherboard. It plugs into a tiny connector on the motherboard. As long as the Matt Card is plugged in (it has to stay plugged in...) the ROM on the Matt Card will be the one that is used. Using the Matt Card is simple. Turn off the Mac, plug in the card, turn on the Mac.
We have many kinds to cater for most models of MacBook Pro retina, MacBook A1534, Mac mini and MacBook Air.
The SPI Activity Monitor is a little board that plugs into the SPI connector of those Macs that have one (MacBook Air & MacBook Pro 'retina'). The SPI-Clock signal is divided by a 12-bit counter and the result is displayed on 12 LEDs. When repairing a motherboard it is nice to know if the EFI-ROM got read. With this tool it is much easier to know if the PCH is running for example.