It was quite difficult to locate this sensor. I have noticed that american vendors do not/have not been including civic ferios (that have the D15B EK3 type engines) in their list of compatible cars. I took a chance and this one works ! This sensor has 4 wires. Two black, one blue and one white. The pinouts corresponds to the OEM, even though the colors were not the same. Its just plug and play. Black(2) is for heater, Blue is for signal, and White is for ground. It even comes with anti-seize compound. IT does not include the rubber grommet that holds the cable in place (mid-way), but you can use other things. IT even looks like the OEM. Quality construction, fits just right. So far so good. I would buy another one at a later date, since my car uses 2. One before the CAT and one after the CAT.After using this sensor for 2 weeks straight and driving at least 100 miles on it, I have have come to the conclusion that using this sensor has increased my fuel consumption. But on the flip side, it has made my idle MUCH smoother and engine more responsive (h/p increase). It does seem incredulous, but I can only report what I have observed. The smoothness in idle has really caught my attention, which is quite an unexpected turn of events. I suppose its a fair trade off, smooth idle that burns a bit more gas - cant win them all !Update: Oct 2012. The sensor is still working like a champ, plus I have been using a lot of intake cleaner to do other maintenance (which sometimes shorten the life of O2 sensors). But so far it keeps on working well. Well worth the money for that price. Dealers price is unbeliveable.Update Aug 2013: still working like a champ. the older O2 heater circuit on the sensor died, so I will install the secondnew O2 sensor this weekend. Great buy !