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: LKR7E, Item: NGK1643, Shell - Thread Diameter: 12mm, Thread Pitch: 1.25mm, Seat Type: Gasket, Reach: 26.5mm (1.04"), Hex Size: 5/8" (16mm), Terminal Type: Solid, Overall Height: ISO, Gap: .035" (0.9mm), Centre Electrode - Material: Nickel, Type: Standard, Size: 2.5mm, Projection: 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.