4 pc DENSO 3121 Standard U-Groove Spark Plugs for M05269899 M04671057 mw

• REDUCE EMISSIONS AND MISFIRES: The patented DENSO Spark Plug enables complete fuel ignition in the combustion chamber. It virtually eliminates erratic starts caused by poor fuel mixtures and excessive soot buildup. The DENSO Spark Plug employs a unique ground electrode designed to generate a larger spark nucleus at the point of ignition. Greater spark energy means improved flame travel, producing more complete, consistent, and efficient combustion
• GAIN GREATER FUEL EFFICIENCY: This DENSO Spark Plug fires leaner mixtures than conventional plugs and improves throttle response. Its ground electrode was developed to improve ignitability for increased efficiency in emission gas purification and fuel consumption. The DENSO Spark Plug is 100 percent pre-fired to ensure reliable operation and lasts twice as long as conventional plugs. The unique five-rib insulator reduces flashover and decreases voltage loss
• RELY ON QUALITY AUTO PARTS: From the development of direct ignition coils to revolutionizing the concept of the aftermarket performance spark plug by using platinum and iridium, DENSO is often on the front lines of product advancement
• TRUST IN DENSO: The automotive industry has recognized the DENSO commitment to quality through such prestigious awards as the Deming Award for Quality, the J.D. Power and Associates Chairman's Award, and numerous supplier awards for quality

DENSO is one of the largest automotive-component suppliers with more than $40 billion in annual sales. For over 65 years, DENSO parts have been the global choice for top automakers, with hundreds of vehicle models rolling off the assembly line with DENSO auto parts under the hood. Combine that with their commitment to quality—showcased by their QS9000 and ISO9000-certified factories and easily installed First Time Fit product line—and you have a clear choice in product reliability and longevity. From the development of direct ignition coils to revolutionizing the concept of the aftermarket performance spark plug by using platinum and iridium, DENSO is often on the front lines of product advancement. DENSO continues their innovation with the First Time Fit® product line, which includes premium DENSO parts such as oxygen sensors, air fuel ratio sensors (AFR), A/C compressors, cabin air filters, condensers, evaporators, radiators, receiver-driers, starters, alternators, fuel pumps, oil and air filters, ignition wire sets, tire pressure monitoring system sensors (TPMS), and windshield wiper blades.

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