DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.