PFERD premium knot cup brush featuring maximum service life, improved balance, and fastest removal rates. Combitwist is a variation on existing knot styles in which the knots are alternately twisted to offer superior balance during rotation. This construction style offers a more aggressive and effective brushing solution for cleaning and deburring applications. More aggressive brushing. Longer brush life. Superior rotational balance. Faster stock removal. Reduced operator fatigue. Better surface finish. Hand-held applications. Less surface area covered. More brush flare. Cup brushes are built with high quality components that are designed to perform in welding and industrial applications. Great cutting action and flexibility, excelling on large flat and curved surfaces. Knot bevel brushes for cleaning hard-to-reach areas. For optimal brushing action, tilt the brush between 15 and 30 degrees off of the workpiece surface. External retaining nut: reduced chance for guard interference, longer overall brush height, easy to access with open end wrench. Provides excellent abrasion and wear resistance, along with high flexing action. High strength filament able to remove heavy buildups. 7/8-inches trim length. 20 knots. Uses in industries area: automotive, transportation, mining, electronics, aerospace, welding, nuclear, textiles, food services, construction, petrochemical, farming, medical, shipbuilding, fabricating, defense, foundries and plastics.