These wire wheel brushes feature 1/4" hex shanks. The hex shank allows their use with quick-change bit holders. Alternatively, the shank offers a more positive grip when used in a standard 3-jaw drill chuck Available either crimped or as a twist knot steel wire wheel. Twisted steel 75mm diameter, crimped steel 50mm diameter . Use for light to medium-duty applications such as cleaning or de-rusting metal surfaces prior to welding or painting. Conforms to DIN EN1083-2 standards.