Derailleur Hanger Fits Trek, Fisher, Mongoose, Schwinn - & Others. Derailleur Hanger Fits Trek, Fisher, Mongoose, Schwinn - & Others. Bicycle manufacturers may make mid year changes. Please use the hanger photos to select the proper hanger for your application ! Derailleur hangers come with the required hardware to attach to the frame ! OEM hangers are only produced by a handful of manufacturers, mostly in Taiwan in China. As a result, you will see many bikes with exactly the same hanger.