Weiler 7″ Roughneck Polyflex Encapsulated Root Pass Weld Cleaning Brush features a heat-stabilized black elastomer that gradually wears exposing consistent short trim for maximum aggression and long-life. Ideal for applications on flat surfaces that require maximum aggression but no flexibility in the brushing action. Suitable for cleaning hot welds. 5/8″-11 nut for use on right angle grinders. Heat stabilized black elastomer gradually wears exposing consistent short trim for maximum aggression and long-life. Ideal for applications on flat surfaces that require maximum aggression but no flexibility in the brushing action. 7/16 in thick at face plate. . .