Pretty simple 25mm rail to mount Tinkerkit boards in. I mounted two Mosfet boards to connect to my printheads, they provide smoother power switching than my Ramps 1.4 board, and can handle running both extruders at once. http://www.digikey.com/product-detail/en/T010020/1050-1090-ND/4486356
Download from thingiverse