Fit perfectly into a 2004 Volvo v70 T5. Removing the old sensor was easy with the proper O2 sensor socket. The connection, on the other hand, was buried deep in this car. Denso provides ant-seize compound that I put on the threads. I also disconnected my battery for 15 minutes and then started it up, and the difference was soon noticeable; smoother running engine, no more gas smell from the exhaust, gas mileage went from 18.5 to 25.1 MPG! Engine is more responsive at all speeds. Volvo calls for O2 sensor replacement at 100k miles, but it will lose efficiency and gas mileage before then. My car had 170k miles on it at replacement. Denso had the best price and it works great. If Amazon had a Denso downstream O2 sensor, I would buy it. But since they didn't I went with a different brand.