Review on Denso SK20R11 Iridium Spark Plug by Bill Pool

I installed them on a 2003 Sienna. As mentioned, the OE spark plugs were NGK IFR6A11. Replacing the three rear plugs on this engine is a PITA, but it can be done - just search online. I had the confidence to do it and it took about 3 hours to replace all 6. They work just as well as the original plugs as expected and are slightly cheaper than the original boot plugs. My only beef was the delivery. They were shipped in a book box with no packaging, so the forks were knocked in transit and some of them fell out of the box. Luckily, the round cardboard protectors protecting the electrodes didn't come off, so the spark plug gaps were intact.