NGK standard plugs are constructed for longer life and optimum performance. Trivalent metal plating provides superior anti-corrosion and anti-seizing properties. Corrugated ribs prevent flashover. Pure alumina silicate ceramic insulator, provides superior strength and better heat transfer. Copper core aids in heat removal. Triple seals prevent leakage. Product Specifications - SKU: DR7EA, Item: NGK7839, Shell - Thread Diameter: 12mm, Thread Pitch: 1.25mm, Seat Type: Gasket, Reach: 19mm (3/4"), Hex Size: 18mm, Terminal Type: Threaded Stud, Overall Height: ISO, Gap: .028" (0.7mm), Centre Electrode - Material: Nickel, Type: Standard, Size: 2.5mm, Projection: Non-Projected, Ground Electrode - Material: Nickel, Type: Standard, Quantity: 1, Specifications - Resistor: Yes, Resistor Value: 5k Ohm, Heat Range: 7, Torque Specs: Cast Iron: 10.8-18 lb ft. Aluminium: 10.8-14.5 lb ft., Part Information - Brand: NGK/NTK, Warranty: 60 Days, Longevity: 30k Miles.