Mercury 889597Q Spark Plug NGK IZFR5The NGK IZFR5G spark plugs come pre-gapped as specified by your engine manufacturer. Use only the spark plug listed in your engine owner's manual. NGK Trivalent metal plating provides superior anti-corrosion in the marine environment and anti-seizing for easier removal.Features Pre-gapped to engine manufacturer specifications; Ribbed suppressor seal prevents spark flashover and misfire; Copper core enhances durability; Trivalent metal plating resists corrosion and seizing, especially in marine environments; Recommended to replace all plugs at the same time; Do not clean used spark plugs; replace with new ones;