... Production of antique stone surfaces Abrasive Brushes are made of high-quality synthetic filaments completely embedded with abrasive grit, which are anchored ... great rigidity lead to an increased production output of natural and artificial stone with antique surfaces. TypeThreadGritFrankfurtsteel,24#,36 ... 60#,80#,120#,180#,240#,320#,500#,800# High Quality Polishing Brush For Marble / Granite / Concrete