Standard Abrasives MD Mini-Brush 875704, 4-1/2 in x 4 in x 5/8-11 FB051 15-46 A VFN Medium Density, 1 per case3M 875704 Standard Abrasives MD Mini Brush, 4 1 2 in x 4 in x 5 8 11 FB051 15 46 A VFN Medium Density, 1 per case. Our Standard Abrasives MD Mini Brush features medium density (MD) Buff and Blend material for efficient restoration of original, high quality finishes on fabricated steel parts. While welds or other imperfections might detract from a fine finish, the original luster can still be salvaged even revitalized and renewed with the help of this