Easy to mount/replacement with the shaft.Working Tool: Variable speed type electric micro grinder.Flannel: laminated buff of soft flannel, optimum for dust removal, final polishing.Materials:Flannel (cloth)Outer Diameter x Shaft Length x Shaft Diameter (mm):20 x 40 x 3Max Working Rotation Speed (rpm):10000Comments:Dust Removal, Final PolishShaft: Free-Cutting Steel