From WikiTemp, the GBAtemp wiki

D2CKey is the latest mod chip for the newly shipped motherboards of the Wii Console. The new motherboards, version d2c, were touted to be unmoddable since the previous chips like Wiikey, Winja,etc. did not work with these new Mobos. But D2Ckey is here and definitely works. Also D2C is the most feature-rich of all the Wii Chips so far. On the downside, it is more expensive and much more difficult to install(31 wires to be soldered against regular 5 wires on other chips)

Update from D2CKey website

Quicker, more streamlined installation of D2CKey!


FlexPcb.png

The FlexPCB for D2CKey streamlines installation of D2CKey reducing the overall time spend fitting the chip. The FlexPCB is available seperately at additional cost.

Although installation with the FlexPCB is quicker, installation of D2CKey is still best left to professional, experienced mod chip installers!