Bosch Double Iridium Spark Plugs feature both an iridium firing pin and an iridium ground electrode inlay that offer higher performance and 4X longer life compared to standard copper spark plugs 360-degree laser welded ultra-fine wire iridium firing pin provides better ignitability - reducing voltage requirements up to 24% - and enhanced durability Nickel-plated rolled threads provide superior resistance to corrosion and do not require anti-seize - making installation quick and easy Bosch Double Iridium spark plugs are pre-gapped at the factory and ready to install right out of the box - gap adjustment prior to installation not required Meets or exceeds manufacturer design requirements for OE fit, form, and function for modern gasoline engines - including Gasoline Direct Injection (GDI) engines Compatible with select vehicles (Note: engine affects fitment - verify specific fitment details with amazon confirmed fit fit checker above): AUDI: 2000-08 A4, 1999-05 A4 Quattro, 2000-04 A6 Quattro, 2001-05 Allroad Quattro, 2002-02 S4, 1999-06 TT Compatible with (continued): AUDI: 2000-06 TT Quattro; BENTLEY: 2006 Continental; CADILLAC: 2014-16 ELR; CHEVROLET: 2010-15 Cruze, 2016 Cruze Limited, 2012-18 Sonic, 2011-15 Volt; MAYBACH: 2003-12 57, 2003-12 62; MERCEDES-BENZ: 2003-14 CL600 Compatible with (continued): MERCEDES-BENZ: 2005-06,2008-14 CL65 AMG, 2014-18 G65 AMG, 2016-17 Maybach S600, 2018-20 Maybach S650, 2022-23 Maybach S680, 2003-13,2015-17 S600, 2006-13,2015-20 S65 AMG, 2017 S65L AMG, 2004-12 SL600 Compatible with (continued): MERCEDES-BENZ: 2005-18 SL65 AMG; MITSUBISHI: 2002-03 Eclipse, 2008-11 Montero; VOLKSWAGEN: 1999-05 Beetle, 1999-06 Golf, 2000-05,2009-10 Jetta, 2000-05 Passat