Hey @trgiezhang ,

I think what you are looking for is a bottom bracket cable guide. ( I think shimano calls it SP-18-T)  REI shops probably have them as a miscellaneous part, but I don't think we sell it on line.  I am sure if you looked at Jenson USA or Nashbar websites they would have them listed. I think they are $2 - $3. so normally i will buy a couple and throw them in a drawer and forget about them.   Its funny how the small common parts are sometimes the hardest to describe.   Hope this helps!!

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