Description DETAILS:Thread Size: M12 Hex Size (mm): 18mm Thread Reach (in): 0.750â Center Electrode Core Material: Copper Approximate Resistor Value (Ohm): 1 Ohm Service #: D8EA Unit of Measure: Each Seat: Flat Heat Range: 8 Preset Gap (in): 0.0028â Number of Ground Electrodes: 1 Center Electrode Tip Material: Nickel Insulator Height (mm): 50mm