I see they don't show those any more on the installation vid or manual. Originally there were a couple different wedge-shaped blocks that fit between the FD fixed portion and the seat tube. You could select one that fit best. AFAICT, the idea was to prevent any flexing of the mount when the FD shifted outboard. Maybe SRAM decided they weren't really needed, but ISTR someone finding that it helped improve shifting. The other problem is sometimes the limit screws are too long and hit the crank arm. SRAM was supplying replacement screws that I guess were shorter.

scott s.
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