A-Pro Services is an Authorized F9 BARC Applicator. An Authorized Applicator has been trained to recognize the different types of rust stains and how to remove them without causing surface damage. Experience combined with proper training and cleaning techniques make a Professional F9 BARC Applicator the right choice for your restoration job. Professional rust removal is an art and a science. Certain rust stains such as irrigation rust stains, rust stains on siding, and rust on shingles are particularly challenging and require expert care so as not to damage the underlying surface.