Any engine needs a spark plug to start. Find just the quality marine-grade spark plugs for your boat engine with Champion Spark Plugs have it for you. Spark Plug L77JC4 821M is a conventional spark plug with electrodes made of a nickel alloy. These Plugs you can count on from Champion Spark Plugs include a copper core electrode for enhanced conductivity and "sure-fire" engine performance. Key Features: OE style replacement plug The triple-coated shell provides outstanding corrosion resistance. Precision-rolled threads meet all manufacturer specifications. The nickel alloy center electrode and ground electrode have excellent wear characteristics. Copper core enhances efficiency and durability. Some plugs filter RFI to safeguard sensitive devices Resistant to overheating under severe load conditions ISO and SAE-certified for performance Specifications: Brand: CHAMPION SPARK PLUGS SKU: 821M UPC: 037551005109 Weight: 0.14 LBS Unit Of Measure: EA Manufacturer Part Number (MPN): 821M Shell Thread Diameter: 14mm Thread Pitch: 1.25mm Seat Type: Gasket Center Electrode Material: Nickel Center Electrode: Type: Standard Size: 2.5mm Projection: Non-Projected Resistor: No Heat Range: 77