What are aluminium drop outs?

I just got a Thule Bike Rack and the User Guide reads: "Do not install bicycles equipped with front forks made from carbon fiber". I emailed the Thule Company and they said that my bike should have aluminium drop outs. Well here is the deal... I have not purchased the bike yet. I'm still looking for the one I want, but I'm sure it will be equipped with front forks made from carbon fiber.


So what are aluminium drop outs?|||the things at the end of the fork, that the wheel actually goes into



these should be metal, not carbon fiber

which i think is usually the case with carbon forks anyway

the ends are usually metal, bonded to the carbon

i think

right?







wle|||Check this picture


http://cdn3.media.cyclingnews.futurecdn.net/2009/08/25/1/rmbs_renovo_dropout_600.jpg|||The drop out is where the axle goes. Most carbon frames are bonded to aluminum drop outs for strength.