NGK Spark Plugs - Brand New BkR5E - 5 pieces BkR6E - 4 pieces Reliable resistor type, green plugs. Example of use: My Subaru Sambar Truck In summer, the BkR6E cold type with a higher heat range. In winter, the BkR5E hot type with a lower heat range. This is just my personal preference and attention to detail... For those who maintain their own vehicles, please consider these.