ALL SPARK PLUGS ARE SOLD INDIVUALLY!! Up for sale is NGK 1999-2002 X1 Lightning Buell SPARK PLUG #4179/10 SOLID. The vendor part number is 4179. Please read the title to know what is for sale SNOW CAT ONLY ILKR8Q7 Spark plug can be used in place of ILKR8Q BPR8ES Spark plug can be used in place of BPR8ES-S