This item is a brand new Variable Valve Timing Solenoid.  Sometimes it is also referred to as a VCT Solenoid.  It will fit the following makes and models with 4.6L and 5.4L Engines:

Note - Must Check Which Seal Your Vehicle Uses Most l Vehicles before 2007 use the one in this listing
1-3/4 Inch Diameter
Compatible with/Replacement for 2005-2006 Expedition
2006-2008 Explorer
2007-2008 Explorer Sport Trac
2004-2007 F150
2005-2007 F250 Super Duty
2005-2007 F350 Super Duty
2005-2006 Mustang
2006-2010 Mark LT
2005-2006 Navigator
2006-2006 Mountaineer
OEM Cross Ref# 3L3Z-6C535-AA