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Features

Laser welded Platinum tip on the centre electrode for improved durability and electrical conductivity
Laser welded Platinum pad or tip (depending on part number) on the ground electrode provides a longer service life
Trivalent metal plating provides superior anti-corrosion and anti-seizing properties
Service life of up to 90,000 miles
Improved cold start performance
Taper-cut ground electrode reduces 'quenching' (helps the flame to expand with minimum amount of obstruction)
Improved idle and smoother acceleration
Better fuel economy and lowers exhaust emissions
Fantastic quality as you'd come to expect from NGK
Original Equipment (OE) approved design

DO NOT USE ANTI-SEIZE LUBRICANT SUCH AS COPPER SLIP ON THE THREADS WHEN FITTING THESE SPARK PLUGS **

Using such thread lubricants can result in over-torqued values by up to 20-25%. Torque wrench readings are rendered completely inaccurate and can result in major damage to the engines cylinder head, or sheer the spark plug threads. Virtually all modern spark plugs feature a special zinc-chromate shell plating which provides corrosion resistance to the elements, so no thread lubricant is required.

Shown below is an over torqued spark plug that sheered due to user installation error. NGK states that incorrect torque values are responsible for up to 90% of all spark plug warranty claims. Incorrect torque can also result in poor engine performance, read below:

Under-torqued spark plugs do not make full contact with the cylinder head which reduces the plug’s ability to transfer heat out of the combustion chamber, this results in elevated combustion temperatures and as such can cause pre-ignition and detonation. These two conditions can lead to engine damage. Evidence of under-torqueing can be seen via the crush washer gasket not being as thin as expected (unless it's a tapered type plug).

Over-torqued spark plugs can cause stress to the metal shell, leading to thread breakage (sheer) as shown in the image below. Over tightening can also compromise the plug’s internal gas seal or even cause a hairline fracture to the insulator. Evidence of over torque is easy to spot, for example hex swelling is visible and usually the crush washer is thinner than expected. If the thread has sheered the breakage will look similar to the spark plug image shown below.
It's advisable to use a good quality, calibration certified torque-wrench. Users should always wind down their torque-wrench to the minimum scale setting and never all the way down after each use. A fully loaded torque wrench left in storage for a long period of time can cause a 'set'in the spring and weaken it. The result can be an inaccurate torque reading.
Care must also be taken to ensure the spark plug socket is not slanted at an angle as this can put pressure on the ceramic insulator causing it to crack.