


⚡ Spark your drive with Bosch’s double iridium power — because your engine deserves the best!
The Bosch 9621 OE Fine Wire Double Iridium Spark Plug features a 360-degree laser-welded ultra-fine iridium firing pin and ground electrode, delivering 4X longer life and up to 24% reduced voltage requirements compared to standard plugs. Nickel-plated rolled threads resist corrosion and eliminate the need for anti-seize, while factory pre-gapping ensures quick, hassle-free installation. Designed to meet or exceed OEM standards, it’s compatible with a wide range of modern gasoline engines, including GDI models from Infiniti, Lexus, Mazda, Nissan, and more.




| Brand | Bosch |
| Core Material | Iridium |
| Thread Size | 12mm |
| Top Material Type | Nickel |
| Vehicle Service Type | Car |
| Global Trade Identification Number | 00028851034258 |
| Automotive Fit Type | Vehicle Specific Fit |
| UPC | 028851034258 |
| OEM Part Number | 9621 |
| Manufacturer | Bosch Automotive |
| Model | Spark Plug |
| Item Weight | 1.44 ounces |
| Product Dimensions | 0.94 x 4.02 x 1.06 inches |
| Item model number | 9621_1 |
| Exterior | Machined |
| Manufacturer Part Number | 9621 |
N**R
A failed product that's not worth buying.
I sent a failed product with a flag that was confirmed by the salesman.
D**S
Quality plug, quality pedigree.
It's very difficult to write a review on spark plugs, as its the type of product that is fitted and ignored or forgotten. All I can say is that the difference to have a new set of plugs fitted compared to those old plugs that have been coughing and spluttering over time, can be noticeable, and your Car will thank you for renewing them, maybe a few more miles to the gallon and less hiccups?. My only suggestion is to stick with a good quality plug such as Bosch, as they will outlive cheaper versions.
A**D
Not recommended, Expected better quality
The picture in the ad is a way of what I found. It's like used or installed before as you can see from the picture the screw lines are not like new and not shiny like new and is not straight there are a little hits on it . Also the packing is very bad and two of it were opened, I did not install it yet but I was expecting to be looked like the pic in the ad. No Recommendation.
D**D
Good product
Works as it should, however the packaging it came in was a flimsy envelope, No protection for theses plugs, luckily none were damaged and they all work really well, my car BMW320i e46 loves these plugs, more responsive and runs nice and smooth.
S**M
Easy to Integrate
I integrated this plug in my Puegeout 306 and it was no hassle and its working fine despite long journeys and daily running.
N**N
Worked a treat!
Worked a treat!! Saved me a lot of money that I would have spent getting a mechanic to do!
Trustpilot
3 weeks ago
5 days ago