NGK G-Power offers the performance and durability of platinum at a competitive price. The center electrode is fine wire platinum for better starts, superior acceleration and better fuel economy. Trapezoid cut ground electrode to reduce quenching. Technical Specifications - GP Single Platinum Spark Plug, 14mm Thread, 19mm (3/4") Reach, 13/16" (20.6mm) Hex Size, Gasket Seat, Resistor, Removable Terminal, JIS Height, Projected Tip, Platinum Tipped Center Electrode, Trapezoid (Beveled Cut) Ground Electrode, .040" (1.016mm) Gap