Weiler 1/4" Pencil End Brush contains straight wire fill material retained in a small diameter steel tube. Provides a light duty brushing action suitable for very small recessed areas. 1/8" stem for use drills and drill presses. Wire end brushes are for use on high-speed portable power tools for addressing smaller surfaces and recessed areas. End brushes are available in a variety of knot wire and crimped wire configurations for use in a broad range of applications, and they are manufactured with the highest quality construction for smooth, efficient performance and long life. Weiler's end brushes are available in heat-treated steel, Type 302 stainless steel, and bronze or brass wire.