parameter of FIX-ZFR6-11,iridium,thread 14mm,reach 19mm (3/4"),hex size 16mm (5/8") , heat range 6, gap 1.1mm (0.44").
Match with NGK , ZFR6F-11,ZFR6FIX-11
Match with DENSO, KJ20CR-L11,IK20L
application chart for automobile,