This set of 8 APR Iridium Pro spark plugs is a superior choice for tuned 4.0 TFSI engines found in the Audi RS6 C7 / RS7 C7 and Audi RS6 C8 / RS7 C8 models. Crafted from Iridium, these spark plugs ensure optimal resistance to temperature and pressure. Their grade 9 APR design provides a stronger spa..