Autolite® Copper spark plugs deliver quick starts, good fuel economy and smooth acceleration. High alumina multi-rib insulator helps prevent flash-over which can lead to misfires One-Piece terminal stud provides a reliable high voltage electrical connection Heat-fused glass composite resistor center seal provides high performance EMI noise suppression and a 100 percent leak-proof seal High nickel alloy side electrode resists electrical and chemical wear providing excellent durability 2 year limited warranty Solid copper core center electrode provides optimal thermal and electrical conductivity for better performance in all driving conditions Package Dimensions: 1.000 x 1.000 x 3.375 inches Package Weight: 0.181 lb Package Quantity: 1 UPC: 009100254627 Center Electrode Core Material: Copper Center Electrode Design: Standard Center Electrode Projection: Mid Projection Center Electrode Tip Material: Nickel Electrical Terminal Type: Stud Ground Electrode Core Material: Nickel Ground Electrode Quantity: 1 Ground Electrode Tip Design: Tapered Ground Electrode Tip Material: Nickel Hex Size: 21 MM Hex Size: 13/16 IN Insulator Material: Ceramic Pre-Gap Size: 0.9 MM Pre-Gap Size: 0.034 IN Reach: 0.5 IN Reach: 13 MM Resistance: 1 82 Resistor Type: No Seat Type: Flat Thread Diameter: 18 MM Country of Origin: CN