hello I am trying to figure out what this part is that has broken on both the front and back breaks of my mountain bike. The part I am mentioning is were the actualy break cable goes through one side of it and down some tubing down to one of the Cantilever breaks. The part had anouther cable that was just attached to it going from the metal disk down to the other cantilever break. What hapened is this cable broke off right below at the edge of the disk. So now I dont have any working breaks on my bike. I have attached an image of the part that is broken. It has the little metal disk that says Shimano on it and you can see were the cable passes through it into the tubing and down to one of the cantilevers. Does anyone know what this part is?