"Least expensive Primary (Upstream) O2 Sensor I could find for my 03 RSX-S. Shipped pretty quickly. Fixed the problems with my idle so my car and took away the Error Code. Now I just need theDenso 234-4360 Oxygen Sensor (Air and Fuel Ratio Sensor)to take away the check engine light completely, and it's only $80.70 on here so I'll be getting that next! GREAT BUY!!!"