Fits 2005-2008 3V heads requiring the 16 mm thread
For use in engines with higher than stock cylinder combustion pressures or sustained high rpm
Unique design is proprietary to Ford 3-valve engines
One heat range colder than the stock Mustang GT plug
Two heat ranges colder than the stock 5.4L-3V truck engine plug
Sold in engine sets of 8

Note:
2008 engines with late style 12 mm spark plugs can be identified by coil engineering number 8L3E
2005-2008 engines with early style 16 mm "High Thread" design spark plugs can be identified by coil engineering number 3L3E part number
All 2009-2010 engines use 12 mm spark plugs