Price is per plug, not a set of 4
The lineup is equivalent NGK No. 8 and No. 9 heat values. New series of plugs inherits the best from existing M series and features Ruthenium Alloy Electrode to provide a reliable spark for all vehicles, including vehicles with increased boost or lightly tuned vehicles.
On top of extended lifetime, use of Ruthenium alloy allows a better fuel burn, resulting in quicker throttle response, smoother idle and better cold starts.
Ruthenium Alloy Center Electrode reduces voltage requirement as well as ignition performance improvement and durability.
Brass Terminal offers film fitting to plug wire or coil-pack.
Plating coating for better insulation and excellent corrosion resistance.
Outer electrode with platinum sqaure chip improves ignition, maximum durability, combustion speed and quality.
The outer electrode has been shortened and engineered with the ideal shape to decrease weight for resistance against vibration.
These are the single best spark plug I have ever ran in the KDM 1.6 and 2.0 turbo engines. Hands down... THE BEST!