To fit the following models
TREK original part no #303978
Cronus - 2011
Cronus CX Pro - 2012
Cronus CX Ultimate - 2012
Cronus CX Ultimate Frameset - 2012
Ion - 2011-2012
Ion CX - 2012
Ion CX Pro - 2012
Ion CX Pro Frameset - 2012
Madone 5 series - 2011
Madone 6 Series - 2010-2011
Speed Concept - 2010-2011
Please compare your hanger to the picture to ensure the correct fitting