Nickel Tt. High ignitability nickel plug (impact of thin diameter on both sides of electrode) A new nickel alloy achieves thin diameter on both sides of the electrode, improving combustion by boosting flame development Boosting flying sparks and ignitability Thin center electrode (1.5mm) Double Needle structure (a first with nickel) Uses nickel alloy with new materials Reasons why the Ni-TT plug can cover for other Nickel plugs The Ni-TT plug can cover for other standard plugs thanks to its better ignitability (flame kernel spreads easily).