Harley Road Glide 1999-2014 Performance Spark Plugs Pair repl. OEM# 6R12 Conventional style spark plugs, available in OEM heat ranges Plugs have a unique look with a black ceramic body Insulator is made of 95% pure alumina, features strong resistance to heat shock and superior insulation Sold in Pairs Harley Road Glide 1999-2014