The NGK Iridium Spark Plug is a game changer. According to my experience, it makes my car engine run more smoothly, increases horsepower and provides better fuel efficiency .The installation process is very easy and it has a longer lifespan than other spark plugs which saves money in the long run. However, the only downside is that it is a bit more expensive than other spark plugs but the pros outweigh the cons. Highly recommended for car enthusiasts..