The NGK 94122 Ruthenium HX Spark Plug features a 5/8 inch wrench diameter and a 14mm spark plug thread size, suitable for various vehicles. It is a glow plug with a gasket style seat and a projected center electrode type. The electrode tip material is ruthenium, known for its durability and efficient spark ignition. With a spark plug reach of 26.50mm (1.043 in.), this high-quality spark plug is designed for optimal performance and longevity in the ignition system of cars and trucks.