Trial-World PM Caliper Mounting Set
Sometimes the PM mountings of frames or forks is not flat. So it is not possible to get the disc free of grinding. It's also possible that a disc has a convex shape, so it's also not possible to get the disc free of grinding, even thought the PM mounting is flat.
With this set of bolts and washers you could tackle the problem.
The washers have a cone, respectively cup shape, so the caliper is slightly inclinable!
The set consists of bolts and washers for one brake caliper.