8 Pack Twisted Knotted Cup Brush for GrindersMaterial and Construction: Both wire wheel brush and cup brush are made of high quality carbon steel, High-quality carbon steel wire is 100% inspected to meet demanding quality specifications,MAX RPM 12,500,suitable for angle grinders with 5 / 8 in 11 NC threaded shank for easy and smooth removal of severe corrosion, rust, paint, spatter and scale, while cleaning the edges of the weld to remove burrs.HIGH QUALITY: 0.020in high-strength hardened carbon steel wire has 4 times better performance than the others in the market, and has perfect knotting integrity.Design: This knotted cup brush thick, knotted cup design is ideal for heavy, aggressive surface treatment of expanded surface areas | the thinner, curly cup design provides maximum flexibility and fatigue resistance, while minimizing the risk of scratches on expanded metal surface areas.APPLICATIONS: Roughening, planing, deburring, honing, structuring, descaling, paint, stripping, weld seams, grinding, polishing and surface treatment of metals.Package List3 Inch knotted wire wheel*44 inch knotted wire wheel*4