Model : G001-06 *A: 1/4" B: 6" C: 3" *Max Drill RPM: 1725 Rpm *Always use eye proction. *Twisted-in-wire brass bristles *Brass bristles will withstand high temperatures of up to 750 °F *Tolerance=+/- 1/32'' for A *Tolerance=+/- 1/4'' for B,C *Brush diameter size A is actual.