PFERD power threaded stringer bead knot wheel brush is tightly twisted for low flex, high impact brushing action. Designed for root and hot pass weld cleaning in pipe joining applications. Also for general use where a narrow face, aggressive brush is desired for controlled, confined surface contact area. Root and hot pass weld cleaning, applications requiring most aggressive brushing action. For optimal performance, use on angle grinders. Knot wheel brushes with threaded hubs for fast and easy tool changes. Superior rotational balance reduces operator fatigue and improves tool life. Provides excellent abrasion and wear resistance, along with high flexing action. High strength filament able to remove heavy buildups. Good bend recovery. 5/8"-11 thread size. 32 knots. 3/4-inches trim length. 3/16-inches face width. Uses in industries area: automotive, transportation, mining, electronics, aerospace, welding, nuclear, textiles, food services, construction, petrochemical, farming, medical, shipbuilding, fabricating, defense, foundries and plastics.