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NGK Iridium Spark Plug Box of 4 (SILKGR9A7EG)

Name: NGK Iridium Spark Plug Box of 4 (SILKGR9A7EG)
Brand: NGK
SKU: ngk91731
Price: 192.40 USD

MPN 91731 · Store SKU ngk91731

$192.40

IN STOCK6 ready to ship

Supplier stock checked 11/7/2026, 7:24:37 AM UTC. Adding a part does not reserve it.

30-day returns for unopened, unused new parts

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

Shipping & returns ↗This policy does not limit rights required by law.

Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.

Product details

NGK Laser Iridium High Ignitability spark plugs offer the best combination of performance and longevity. Engineered specifically for OE applications, Laser Iridium High Ignitability spark plugs are tested to the highest standards to ensure quality and durability. Iridium tipped center electrode provides durability six times harder than platinum. NGKs high grade pure alumina ceramic and 98 percent pure copper core prevents the spark plug from overheating while providing reliable starts. Laser Iridium High Ignitability spark plugs feature raised platinum pad or platinum fine wire tip on the ground electrode for even wear in distributorless ignition systems and improved spark performance. NGK Laser Iridium 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. NGK Laser Iridium High Ignitability spark plugs offer the most advanced OE spark plug tip technology providing the optimal combination of performance and durability. Actual OE or equivalent replacement spark plugs. NGK Laser Iridium High Ignitability Spark Plug

Manufacturer fitment & guides

2014-13 Mercedes-Benz C300, 2014-12 Mercedes-Benz C350, 2015 Mercedes-Benz C400, 2020-17 Mercedes-Benz C43 AMG, 2016 Mercedes-Benz C450 AMG, 2020-14 Mercedes-Benz CLA45 AMG, 2017-15 Mercedes-Benz CLS400, 2016-14 Mercedes-Benz E300, 2016-12 Mercedes-Benz E350, 2018-14 Mercedes-Benz E400, 2018-17 Mercedes-Benz E43 AMG, 2020-19 Mercedes-Benz E450, 2016-15 Mercedes-Benz GL450, 2019-15 Mercedes-Benz GLA45 AMG, 2020-17 Mercedes-Benz GLC43 AMG, 2018-16 Mercedes-Benz GLE350, 2019-16 Mercedes-Benz GLE400, 2019-17 Mercedes-Benz GLE43 AMG, 2016 Mercedes-Benz GLE450 AMG, 2018-16 Mercedes-Benz GLE550e, 2019-17 Mercedes-Benz GLS450, 2015-12 Mercedes-Benz ML350, 2015 Mercedes-Benz ML400, 2020-18 Mercedes-Benz S450, 2017-15 Mercedes-Benz S550e, 2020-19 Mercedes-Benz S560e, 2016-15 Mercedes-Benz SL400, 2020-17 Mercedes-Benz SL450, 2020-17 Mercedes-Benz SLC43 AMG

Manufacturer-supplied application summary from Turn14; this may not be an exhaustive fitment list.

A manufacturer application guide is not available for this listing. Request the exact application from JuiceBuilt before payment.

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What is the return policy?

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

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This policy does not limit rights required by law.

NGK Iridium Spark Plug Box of 4 (SILKGR9A7EG)

Product details

Manufacturer fitment & guides

THE NEXT PART
OF YOUR BUILD.

Free shipping on $100+ orders.

Build with the right brands.

Find your next upgrade.

Make the whole setup work.

A few things to know.

Your build.

Delivery & checkout

Delivery address