Mercury 883323001 Spark Plug RA8HC The 810 Spark Plug provides increased conductivity and heat control for goof overall wear by its star feature copper core electrode. The 810 is known for its dependable performance and durability. The spark plug provides superior corrosion resistance and resists fouling. Mercury Outboard Application Information For 40 HP 3 Cyl Fourstroke 1C049739 and above, 40-50-60 HP Fourstroke 1C050252 and above. Interchangeable with Champion RA8HC California Residents WARNI