Help identfying part and its function

[Strider84]

Hi all,

I've had shifting issues with rear derailleur have tried cleaning existing components and reindexing but having trouble shifting down into the lowest cog without having cable tension so slack that I can't shift up the cassette. So figured I would replace the cable ferrules and outer cables. The one thing I am struggling to find is the bit pictured below. The top pic is of it insitu the ferrule type piece goes into the frame but coming out of the ferrule is a thin black coating that the piece on the right then covers when it is insitu. I'm guessing these are in place to prevent dirt getting into the cable housing? Just can't find any reference to them online and unsure whether I even need to replace them.


Thanks in advance

 

[fossyant]

You've got new inners too.

You can reuse that black seal if you want. Make sure its clean before fitting. You don't need to have it though.

 

[I like Skol]

Shimano mtb cable kits come with the rubber booty thing included

 

[Specialeyes]

Your best-bet search term is 'mtb cable gaiter'

 

[Ajax Bay]

Not on topic - but I would check your rear mech hanger alignment as the symptoms you described early on are consistent with the hanger being bent in a bit, as quite easily happens.