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Geekstop

Arctic Cat Harley-Davidson Kawasaki Textron Triumph Yamaha NGK 3521 CR9EIX Iridium IX Spark Plug 6pcs

Arctic Cat Harley-Davidson Kawasaki Textron Triumph Yamaha NGK 3521 CR9EIX Iridium IX Spark Plug 6pcs

$29.80 USD
$63.30 USD $29.80 USD
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SKU: NGK3521
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Description

NGK 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

Shell

  • Thread Diameter10mm
  • Thread Pitch1.0mm
  • Seat TypeGasket
  • Reach19mm (3/4")
  • Hex Size5/8" (16mm)
  • Terminal TypeRemovable Nut
  • Overall HeightISO
  • Gap.031" (0.8mm)

Center Electrode

  • MaterialIridium
  • TypeFine Wire
  • Size0.6mm
  • ProjectionNon-Projected

Ground Electrode

  • MaterialNickel
  • TypeStandard
  • ShapeTaper Cut
  • Quantity1

Specifications

  • ResistorYes
  • Resistor Value5k Ohm
  • Heat Range9
  • Torque SpecsCast Iron: 7.2-10.8 lb. ft. Aluminum: 7.2-8.7 lb. ft.

Warranty & Returns

Geekstop Limited Warranty

Clear, year-based coverage and a simple claim process—buy with confidence.

Parts-only warranty
Original purchaser only
Non-transferable

Brake Rotors / Drums

10 Year Warranty

Material & workmanship coverage with proper bedding/torque.

Wheel Hub & Bearing Assemblies

10 Year Warranty

Coverage requires correct torque/alignment; impact damage excluded.

Suspension & Control Arms

10 Year Warranty

Ball joints/tie rods/control arms under normal, listed use.

Coverage by Part Category

Category Warranty Notes
Brake Rotors / Drums 10 Year Warranty Material & workmanship; thermal cracking excluded if outside bedding/torque specs.
Wheel Hub & Bearing Assemblies 10 Year Warranty Proper torque & alignment required; press/impact damage excluded.
Control Arms / Ball Joints / Tie Rods 10 Year Warranty Boot tears from road impact and altered parts are excluded.
Ceramic / Semi-Metallic Brake Pads Workmanship 90 Days Friction wear is consumable and not covered; noise/dust vary by use.
Struts / Shocks 10 Year Warranty Leaks due to physical damage or overload are excluded.

Coverage applies to the original retail purchaser and is non-transferable. Commercial/fleet use requires written approval on the order.

What’s Covered

  • Manufacturing defects in materials or workmanship
  • Premature failure under normal, listed use
  • Fitment issues for the advertised application
  • Replacement of the defective part(s) after inspection
  • Return shipping on approved claims

What’s Not Covered

  • Normal wear items (pads/shoes/filters)
  • Improper installation, missing bedding or torque to spec
  • Racing/off-road/overload, accident or impact damage
  • Corrosion from chemicals/road salt, environmental exposure
  • Modified parts, misuse, or no proof of purchase

How to File a Warranty Claim

1) Start a Claim
Email karly@geekstopbrakes.com with your order number, issue summary, and contact info. We respond within 24–48 hours.
2) Provide Documentation
Photos/video of the issue, proof of purchase, mileage at failure, and any install details (shop or DIY).
3) Return Authorization (RMA)
We issue an RMA and instructions. Approved claims include a prepaid return label.
4) Inspection & Resolution
We verify eligibility against this policy. Approved claims receive a replacement or refund within 5–7 business days.
Need help? Our warranty team is here to assist. Include clear photos and details—that speeds up approval.
Contact Warranty Support
Response: 24–48 hours
Mon–Fri, 9 AM – 6 PM EST

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