Vikan 53915 3.5in pipe brush for flex rod- medium, white tube brushes for flexible handles are a great solution for cleaning machinery and equipment with narrow valves, pipes, and other parts. This full-bristle tube brush cleans many commonly sized tubes and valves. The specialized thread on this brush fits the vikan long flexible handles 5350 and 53525. The bristles are dense and firm enough to clean thoroughly, but flexible enough to move with the shape of the equipment being cleaned.