Features NYLON BRUSH (- Tube ID 1/4"-4" & 5"-14") Used to remove the soft scale deposits & polishing purpose in ferrous & non ferrous tubes. BRASS BRUSH (-Tube ID 1/4"-4") Used to remove the soft & light sale deposits from non-ferrous tubes. STAINLESS STEEL BRUSH(-Tube ID 1/4"-4") Used to remove the soft & light scale deposits & from ferrous tubes.