mystery clamp Help

[utlucky]

I have a specialized allez sport, I was cleaning the bike last night and there is a black plastic clamp type thing sliding around between the bottom bracket and f derailleur. I cant for the life figure out its purpose. Anyone with this model of bike that can take a look and let me know.
Thanks

 

[Scotty_Dog]

Is it like what is pictured in this old post:

http://www.cyclingforums.com/showthread.php?p=3310319&highlight=tooth#post3310319

 

[utlucky]

That's it, now it becomes so obvious
thank you