NGK Iridium IX Spark Plugs BKR5EIX-11 # 5464 Set of 4 I purchased and imported these from AliExpress for my personal Subaru Pleo because it was making a popping sound at low speeds. After replacing them, the idling became stable. Install by hand-tightening until resistance is met, then tighten an additional 1/2 to 2/3 turn with a spark plug wrench. Wrench size is M14. Suitable for Subaru R2, Sambar, Pleo, etc. Many other manufacturers also have compatible models. The following site is convenient for compatibility checks: https://www.rakuten.ne.jp/gold/auc-138onlineshop/NGKPlug/INDEX.html