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Four HKS spark plugs on a white background

HKS 50003-M45XL M-Series Racing Spark Plug M45XL Heat Range 45 (4 pack)

SKU HKS-50003-M45XLx4
by HKS
Save $ 0.88 Save $ 0.88
$ 119.88
$ 119.88 - $ 119.88
$ 119.88
$ 119.00
$ 119.00 - $ 119.00
$ 119.00

HKS 50003-M45XL M-Series Super Fire Racing Spark Plug (M45XL) – 4 pack

Genuine HKS Super Fire Racing M-Series spark plug designed for stable ignition and durability in demanding, high-load performance applications. M-Series plugs feature HKS-specific anti-fouling and durability design elements for performance-oriented engines.

Part Number

  • HKS: 50003-M45XL

  • Model: M45XL (XL Type)

Key Features (per HKS M-Series)

  • 0.6mm iridium alloy center electrode for focused spark energy and long service life

  • Platinum-tipped ground electrode for improved durability

  • Short-type / anti-vibration ground electrode design to help withstand harsh conditions

  • Anti-fouling design features (Thermal Edge & Spark Support Gap) to help reduce carbon buildup

Specifications (M45XL)

  • Heat Range: HKS 45

  • Thread Size / Reach: 12mm x 26.5mm

  • Hex / Wrench Size: 16mm

 

Please confirm fitment before purchase. Spark plug compatibility depends on your engine’s required thread/reach, seat type, heat range, and your tune/setup.

To verify fitment, match your application to these specs:

  • 12mm thread

  • 26.5mm reach

  • 16mm hex

  • HKS heat range 45

  • Professional installation recommended

  • Use proper torque and gap per your engine/tuner specifications