This very basic component implements the Rolling Ball Fillet from Rhino Common. Using two surfaces and corresponding UV point values to define the relative location of the fillet on the a single radius and tolerance value can be provided, resulting in a new surface or list of surfaces. The output is currently very limited in that it only provider resulting fillet surfaces, but does not trim back the original surfaces or provide any other output data. The component, much like the actual fillet surface command, will also unexpectedly fail on occasion, as can happen in the example grasshopper file, returning nothing.