Spark Plug Information:
PZNAR6A11H -Platinum
ZNAR6AIX-11 -Iriduim

PART NUMBER 42126 M12x1.25x21mm Taper Seat spark plug insert.
repairs spark plugs in some of the 2008 Lincoln Mark LT and
2008 Ford F-450 Super Duty Lariat, XL, XLT 6.8 V10.
2008 Ford Explorer Eddie Bauer, Limited, XLT 4.6 V8
2009 F-150 Pick ups 4.6 V8. Please verify your spark plug size
to be sure it uses the new M12x1.25 taper seat plugs.

Use Spark plug kit M12x1.25 p/n 4212H tooling to install
special M12x1.25x21mm taper seat insert p/n 42126
5 inserts and sealer is included in p/n 4212H kit.

NGK PZNAR6A11H

Link to Ford 3 vavle M12x1.25 spark plug kit page