NGK Spark Plug - ILFR6GE - #4212. The NGK ILFR6GE (#4212) spark plug is engineered for modern, high-performance engines that demand consistent ignition, long service life, and dependable cold starts. As an original equipment plug in many late-model applications, this premium design delivers the durability and firing precision required for today's advanced ignition systems.. Built with a fine-wire iridium center electrode, the ILFR6GE provides a strong, focused spark that improves combustion efficiency and helps maintain stable idle quality. Iridium's extreme hardness allows for a smaller diameter electrode without sacrificing strength, resulting in improved ignitability and longer plug life compared to traditional copper or standard platinum plugs.. To further enhance longevity, this spark plug features platinum on the ground electrode, adding an extra layer of protection against wear and gap erosion. This dual precious-metal construction helps maintain proper spark gap over time, redu