Inner dia / tube cleaning brushes Are designed for use on portable tools and drill MACHINE. They provide hard-working brush action for fast, thorough cleaning, DEBURRING and finishing in such hard-to-reach places as small diameter holes, deburring recesses, internally threaded surfaces, and many otherwise inaccessible areas. Fill materials include steel, stainless steel, brass, nylon abrasive filament and nylon. The particular purposes of tube cleaning brushes are to de-rust, clean and de-scale the insides of tubes. They are used for manual processing and in flexible shafts and static machines.