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NGK Iridium IX Iridium Spark Plugs Thread Size 10mm (Set of 4) - 3521 CR9EIX

NGK Iridium IX Iridium Spark Plugs Thread Size 10mm (Set of 4) - 3521 CR9EIX

4 pcs Spark Plugs
NGK 3521 CR9EIX IX Iridium Plug
ITEM : # NGK3521
0.6mm Center Electrode
Enhanced Ignitability
Trivalent Metal Plating

NGK's IX Iridium Series Plugs were Designed Specifically for the Performance Enthusiast.

Fine Wire Center Electrode Ensures High Durability and a Consistently Stable Spark
Iridium Alloy has an Extremely High Melting Point, Perfect for Today's High-Tech, High Performance Engines
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


Thread Size: 10mm
Thread Pitch: 1.0mm
Seat Type: Gasket
Resistor: Yes
Resistor Value: 5K Ohm
Reach: 19mm (3/4")
Hex Size: 5/8" (16mm)
Terminal Type: Threaded Stud
Overall Height: ISO
Gap: .031" (0.8mm)

Center Electrode

Material: Iridium
Type: Fine Wire
Size: 0.6mm
Projection: Non-Projected

Ground Electrode

Material: Nickel
Type: Standard
Shape: Taper Cut
Quantity: 1


Torque Specs: Cast Iron: 7.2-10.8 lb. ft. Aluminum: 7.2-8.7 lb. ft.
Brand: NGK
Heat Range: 9
Longevity: 40-50k

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