Please note that we discontinued the sale of NGK spark plugs as we now offer better spark plugs for these cars -- the Brisk Premium LGS plugs!The IS-F Yamaha/Toyota V6 runs extremely hot under track conditions. We recommend upgrading to 1 step colder plugs. NGK Iridium are know to be the best quality Iridium plug you can buy. As an added benefit, NGK Iridiums are common to many applications, and are therefore more reasonably priced than the OEM Denso plugs. Fit and Compatibility: Lexus IS250/300/350 2006+Lexus RC300/350 2015+Lexus GS350 2006+