DENSO spark plugs - U27FER9. Picture shows U27ETR but U27FER9 are similar. Made in Japan/China. Honda NC30 supplied with Denso Y27FER-C plugs. He wants us to use the standard Denso Y27FER-C plugs in the front 2 cylinders and the Denso Y31FER-C in the rears due to them running hotter.
