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Denso Iridium Spark Plug 3421Shop All DENSO
Part # 3421
SKU # 533116
Price Not Available
Center Electrode Tip Material
Manufactured to OEM quality standards.
- DENSO patented optimized iridium-rhodium alloy formula: highest concentration of iridium vs competitors for greater durability
- Extra long life spark plugs manufactured to OEM service interval specifications
- OE style iridium with iridium alloy center electrode (90% Ir) & platinum ground strap
- DENSO patented 360 degree laser welding process: ensuring exceptional quality bond and structural strength with the iridium center electrode
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