this is just for the harness ONLY. the e-manage ultimate unit is sold. simple plug in and play. havent used it myself cause i've changed my mind and decided to run an Apexi PowerFC. it plugs straight up to the PowerFC so no problems with the r34 ecu's. it comes with EVERYTHING needed, even certain requirement so the e-manage doesn't fry your coilpacks. Greddy never made a harness for the er34, this was made up for the er34 by previous owner. great for those guys, especially the auto (use to be an auto, was hunting around for yonks), wanting to run the Greddy e-manage ultimate. saves you/tuner time and money having to wire up a universal harness to your r34. price is $200 ono + postage.