Any good Boy Scout can tell you the value of being prepared. Having a spare derailleur hanger in your tool kit is essential if you're an active cyclist with events on your calendar. After all, these are designed to fail in the event of a crash. Your frame and top dollar rear derailleur will be spared from breakage, and the fix is cheap and easy. That is, if you have the spare. This Ridley Noah R Flow 2009 Derailleur Hanger is made of aluminum and comes with fresh hardware for installation. It fits 2009 and newer Noah frames.