OE Style Double Protection Cover and refined zirconia element maintain proper unit temperature for quicker response times and protect the ceramic element against silicone and lead poisoning. Aluminum-Oxide Trap Layer keeps silicone and lead outside the ceramic element through DENSO's exclusive design, preventing damage to the platinum electrode. Corrosion-resistant stainless steel housing blocks contamination with a rugged, watertight body. Porous PTFE Filter allows atmospheric oxygen to enter the sensor without permitting water or efficiency-robbing engine contaminants to seep into the casing. Increased performance and efficiency and reduced fuel consumption. First Time FitŪ delivers the right part the first time #1 Cylinder is the Key to Locating the Oxygen Sensor DENSO Warranty Information 12 month. IMPORTANT A/C COMPRESSOR WARRANTY NOTE: In order to ensure that proper warranty credit is issued if needed, the compressor installation instructions must be adhered to. All compressor defects must show proof of purchase of an Orifice Tube/Expansion Valve, Drier, and Approved A/C System Flush or a Work Order showing the purchase of these items and that the system was flushed using approved procedures.