Your choice of the spark plug should aid in maximizing engine performance. Spark Plugs UL18V (824). These Champion Spark Plugs enhance the engine performance of all models of personal watercraft. Copper Plus spark plugs include a copper core center electrode that permits precise control of the heat range, boosting performance and prolonging the plug's lifespan. Key Features: Triple-coated shell provides superior corrosion protection. Industry's most robust triple-seal assembly. A patented Ultraseal cover prevents corrosion. Effortless start and quicker throttle response Precision-rolled threads meet all manufacturer specifications. Copper core enhances efficiency and durability. RFI suppression to safeguard electronics. Heat-active under intense engine loads, alloy resists overheating. Specifications: Brand: Champion Spark Plugs SKU: 824 UPC: 037551151868 Weight: 0.14 LBS Manufacturer Part Number (MPN): 824 Type: Copper Plus Thread Diameter: 14mm Thread Pitch: 1.25mm Seat Type: Gasket Reach: 12.7mm (1/2") Hex Size: 13/16" (21mm) Terminal Type: Solid Center Electrode Material: Nickel Type: Standard Size: 2.5mm Projection: Non-Projected Ground Electrode Type: Surface Discharge Resistor: No Heat Range: 18