Double ends allow for large surface scrubbing on one end and precision cleaning with the smaller end. 
 
3 Pack All Purpose Brush
2-Nylon All Purpose Brush
1-Blue Nylon All Purpose Brush
 
The nylon brushes are the least aggressive, meet Mil. Spec. and are safe for everyday use. Recommended for use on virtually any surface including wood surfaces.
 
The Blue Nylon Brush features stiff bristles that allow for a more aggressive clean.