parameter of AIX-LFR6-11,iridium,thread 14mm,reach 26.5mm (1.04"),hex size 16mm (5/8") , heat range 6, gap 1.1mm (0.44").
Match with NGK ,LF6RA-11,LFR6AIX-11
Match with DENSO, K20HR-U11,IKH20
application chart for automobile,