This is a derailleur hanger for the following Cannondale bikes: 2009 29er 1 2009 29er 4 2007 Adventure Series 2007 CAAD2 2007 CAAD3 2007 CAAD4 2007 CAAD5 2007-2009 Comfort Series 2008 Cross XR4 2008 Cross XR6 2009-2010 CX 9 2009-2010 Cyclocross 2007 Daytripper 2007 Hybrid 2001-2004 Jekyll 1991-2006 Mountain 1991-2006 MT Tandem 2007 Optimo 2007 Raven 2010 Red 2008 Road Warrior 1/2 2007-2009 Street Series 2007 Super-V 2007 Touring 2009-2010 Touring 1/2