NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode's durability is six times harder than platinum. Iridium alloy's extremely high melting point is perfect for today's engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug. NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. HON/ACU 2004-92; CHEV/PONT 2008-90; CHRYS/DOD2005-92; FORD/LINC/MERC 2006-89; HYU/KIA 2012-93; JAG 2007-97; MAZ 2014-90; M-BENZ 2008-98; MITSU 2007-92; NIS/INF 2004-90; SATURN 2002-91; SUBARU 2010-95; TOY/LEX/SCI 2014-90; ATV - 2008-05 HON